This adds metadata updates to the same write batch as the underlying
file change. The odds of a metadata update going missing is greatly
reduced.
Bonus change: actually commit the transaction in recalcMeta.
lib/db: Recover sequence number and metadata on startup (fixes#6335)
If we crashed after writing new file entries but before updating
metadata in the database the sequence number and metadata will be wrong.
This fixes that.
We could potentially get a snapshot and then fail to get a releaser,
leaking the snapshot. This takes the releaser first and makes sure to
release it on snapshot error.
The readWriteTransaction offered both commit() (the one to use) and
Commit() (via embedding) where the latter didn't close the read
transaction. This removes the lower cased variant in order to prevent
the mistake.
The only place where the mistake was made was the new gc runner, where
it would leave a read snapshot open forever.
During some other work I discovered these tests weren't great, so I've
rewritten them to be a little better. The real changes here are:
- Don't play games with not starting the folder and such, and don't
construct a fake folder instance -- just use the one the model has. The
folder starts and scans but the folder contents are empty at this point
so that's fine.
- Use a fakefs instead of a temp dir.
- To support the above, implement a fakefs option `?content=true` to
make the fakefs actually retain written content. Use sparingly,
obviously, but it means the fakefs can usually be used instead of an
on disk real directory.
This adds a new config with the simple and concise name
maxConcurrentIncomingRequestKiB. This limits how many bytes we have "in
the air" in the form of response data being read and processed.
After some testing I think that not having this limiter is seldom a
great idea and thus I propose a default value of 256 MiB for this new
setting.
I also refactored the folder IO limiter to be a model/folder attribute
instead of a package global.
Adds a new folder state "Waiting to Sync" in the same vein as the
existing "Waiting to Scan". This vastly improves performances in the
rare cases when there are lots and lots of folders operating.
Also retain the interval over restarts by storing last GC time in the
database. This to make sure that GC eventually happens even if the
interval is configured to a long time (say, a month).
* lib/db: Deduplicate block lists in database (fixes#5898)
This moves the block list in the database out from being just a field on
the FileInfo to being an object of its own. When putting a FileInfo we
marshal the block list separately and store it keyed by the sha256 of
the marshalled block list. When getting, if we are not doing a
"truncated" get, we do an extra read and unmarshal for the block list.
Old block lists are cleared out by a periodic GC sweep. The alternative
would be to use refcounting, but:
- There is a larger risk of getting that wrong and either dropping a
block list in error or keeping them around forever.
- It's tricky with our current database, as we don't have dirty reads.
This means that if we update two FileInfos with identical block lists in
the same transaction we can't just do read/modify/write for the ref
counters as we wouldn't see our own first update. See above about
tracking this and risks about getting it wrong.
GC uses a bloom filter for keys to avoid heavy RAM usage. GC can't run
concurrently with FileInfo updates so there is a new lock around those
operation at the lowlevel.
The end result is a much more compact database, especially for setups
with many peers where files get duplicated many times.
This is per-key-class stats for a large database I'm currently working
with, under the current schema:
```
0x00: 9138161 items, 870876 KB keys + 7397482 KB data, 95 B + 809 B avg, 1637651 B max
0x01: 185656 items, 10388 KB keys + 1790909 KB data, 55 B + 9646 B avg, 924525 B max
0x02: 916890 items, 84795 KB keys + 3667 KB data, 92 B + 4 B avg, 192 B max
0x03: 384 items, 27 KB keys + 5 KB data, 72 B + 15 B avg, 87 B max
0x04: 1109 items, 17 KB keys + 17 KB data, 15 B + 15 B avg, 69 B max
0x06: 383 items, 3 KB keys + 0 KB data, 9 B + 2 B avg, 18 B max
0x07: 510 items, 4 KB keys + 12 KB data, 9 B + 24 B avg, 41 B max
0x08: 1349 items, 12 KB keys + 10 KB data, 9 B + 8 B avg, 17 B max
0x09: 194 items, 0 KB keys + 123 KB data, 5 B + 634 B avg, 11484 B max
0x0a: 3 items, 0 KB keys + 0 KB data, 14 B + 7 B avg, 30 B max
0x0b: 181836 items, 2363 KB keys + 10694 KB data, 13 B + 58 B avg, 173 B max
Total 10426475 items, 968490 KB keys + 9202925 KB data.
```
Note 7.4 GB of data in class 00, total size 9.2 GB. After running the
migration we get this instead:
```
0x00: 9138161 items, 870876 KB keys + 2611392 KB data, 95 B + 285 B avg, 4788 B max
0x01: 185656 items, 10388 KB keys + 1790909 KB data, 55 B + 9646 B avg, 924525 B max
0x02: 916890 items, 84795 KB keys + 3667 KB data, 92 B + 4 B avg, 192 B max
0x03: 384 items, 27 KB keys + 5 KB data, 72 B + 15 B avg, 87 B max
0x04: 1109 items, 17 KB keys + 17 KB data, 15 B + 15 B avg, 69 B max
0x06: 383 items, 3 KB keys + 0 KB data, 9 B + 2 B avg, 18 B max
0x07: 510 items, 4 KB keys + 12 KB data, 9 B + 24 B avg, 41 B max
0x09: 194 items, 0 KB keys + 123 KB data, 5 B + 634 B avg, 11484 B max
0x0a: 3 items, 0 KB keys + 0 KB data, 14 B + 17 B avg, 51 B max
0x0b: 181836 items, 2363 KB keys + 10694 KB data, 13 B + 58 B avg, 173 B max
0x0d: 44282 items, 1461 KB keys + 61081 KB data, 33 B + 1379 B avg, 1637399 B max
Total 10469408 items, 969939 KB keys + 4477905 KB data.
```
Class 00 is now down to 2.6 GB, with just 61 MB added in class 0d.
There will be some additional reads in some cases which theoretically
hurts performance, but this will be more than compensated for by smaller
writes and better compaction.
On my own home setup which just has three devices and a handful of
folders the difference is smaller in absolute numbers of course, but
still less than half the old size:
```
0x00: 297122 items, 20894 KB keys + 306860 KB data, 70 B + 1032 B avg, 103237 B max
0x01: 115299 items, 7738 KB keys + 17542 KB data, 67 B + 152 B avg, 419 B max
0x02: 1430537 items, 121223 KB keys + 5722 KB data, 84 B + 4 B avg, 253 B max
...
Total 1947412 items, 151268 KB keys + 337485 KB data.
```
to:
```
0x00: 297122 items, 20894 KB keys + 37038 KB data, 70 B + 124 B avg, 520 B max
0x01: 115299 items, 7738 KB keys + 17542 KB data, 67 B + 152 B avg, 419 B max
0x02: 1430537 items, 121223 KB keys + 5722 KB data, 84 B + 4 B avg, 253 B max
...
0x0d: 18041 items, 595 KB keys + 71964 KB data, 33 B + 3988 B avg, 101109 B max
Total 1965447 items, 151863 KB keys + 139628 KB data.
```
* wip
* wip
* wip
* wip
Makes the logic a bit clearer and safer. This also sneakily redefines
the 0 interval to also mean disabled, whereas it previously meant ...
sometimes default to 1s, sometimes just spin.
* lib/db, lib/protocol: Compact FileInfo and BlockInfo alignment
This fixes the following two lint warnings
FileInfo: struct of size 160 bytes could be of size 136 bytes
BlockInfo: struct of size 48 bytes could be of size 40 bytes
by reordering fields in alignment order (64 bit fields, then 32 bit
fields, then 16 bit fields (if any), then small ones). The end result is
a slightly less aesthetically pleasing struct field order, but since
these are the objects we often juggle in bulk and keep large queues of I
think it's worth it.
It's a micro optimization, but a cheap one.
This adds error returns to model methods called by the protocol layer.
Returning an error will cause the connection to be torn down as the
message couldn't be handled. Using this to signal that a folder isn't
currently available will then cause a reconnection a few moments later,
when it'll hopefully work better.
Tested manually by running with STRECHECKDBEVERY=0 on a nontrivially
sized setup. This panics reliably before this patch, but just causes a
disconnect/reconnect now.
As foretold by the prophecy, "once the database refactor is merged, then
shall appear a request to propagate errors from the store known
throughout the land as the NamedspacedKV, and it shall be good".
This PR does two things, because one lead to the other:
- Move the leveldb specific stuff into a small "backend" package that
defines a backend interface and the leveldb implementation. This allows,
potentially, in the future, switching the db implementation so another
KV store should we wish to do so.
- Add proper error handling all along the way. The db and backend
packages are now errcheck clean. However, I drew the line at modifying
the FileSet API in order to keep this manageable and not continue
refactoring all of the rest of Syncthing. As such, the FileSet methods
still panic on database errors, except for the "database is closed"
error which is instead handled by silently returning as quickly as
possible, with the assumption that we're anyway "on the way out".
* lib/versioner: Reduce surface area
This is a refactor while I was anyway rooting around in the versioner.
Instead of exporting every possible implementation and the factory and
letting the caller do whatever, this now encapsulates all that and
exposes a New() that takes a config.VersioningConfiguration.
Given that and that we don't know (from the outside) how a versioner
works or what state it keeps, we now just construct it once per folder
and keep it around. Previously it was recreated for each restore
request.
* unparam
* wip
We incorrectly gave a too small buffer to lz4.Compress, causing it to
allocate in some cases (when the data actually becomes larger when
compressed). This then panicked when passed to the buffer pool.
This ensures a buffer that is large enough, and adds tripwires closer to
the source in case this ever pops up again. There is a test that
exercises the issue.
* gui, lib/api: Adds support for prefers-color-scheme on default theme (fixes#6115)
- Renames current default theme into a new "light" theme
- Modifies assets serving to allow getting assets from different themes
* lib/api: Serve assets from arbitrary theme when path starts with "theme-assets"
* lib/api: Moves constant out of function
* Loads light theme in browsers without support for prefers-color-scheme
* gui: Disables dark theme when printing
* Prevents repeated injection and adds support for older browsers
The CSS is always loaded if there is no support for `matchMedia`.
* Fix bufferpool puts (ref #4976)
There was a logic error in Put() which made us put all large blocks into
segment zero, where we subsequently did not look for them.
I also added a lowest threshold, as we otherwise allocate a 128KiB
buffer when we need 24 bytes for a header and such.
* wip
* wip
* wip
* wip
* wip
* wip
* wip
* wip
* wip
* wip
* smaller stress
* cap/len
* wip
* wip
This adds a certificate lifetime parameter to our certificate generation
and hard codes it to twenty years in some uninteresting places. In the
main binary there are a couple of constants but it results in twenty
years for the device certificate and 820 days for the HTTPS one. 820 is
less than the 825 maximum Apple allows nowadays.
This also means we must be prepared for certificates to expire, so I add
some handling for that and generate a new certificate when needed. For
self signed certificates we regenerate a month ahead of time. For other
certificates we leave well enough alone.
The relay and discosrv didn't use the new lib/build package, now they
do. Conversely the lib/build package wasn't aware there might be other
users and hard coded the program name - now it's set by the build
script
This adds a field `guiAddressUsed` to the system status response, that
holds the current listening address actually in use. This may be
different from the one stored in the config because it may have been
overridden by environment or command line flag.
The GUI now checks this field to see if we are listening on localhost.
If we are not, the authentication required warning is displayed,
regardless of the *configured* listening address.
This is an experiment in testing, based on the advise to always call
t.Parallel() at the start of every test. Doing so makes tests run in
parallel, which is usually faster, but also exposes package level state
and potential race conditions better.
To support this I had to redesign the CSRF manager to not be package
global, which was indeed an improvement. And tests run five times faster
now.
This splits large writes into smaller ones when using a rate limit,
making them into a legitimate trickle rather than large bursts with a
long time in between.
This is the result of:
- Changing build.go to take the protobuf version from the modules
instead of hardcoded
- `go get github.com/gogo/protobuf@v1.3.0` to upgrade
- `go run build.go proto` to regenerate our code
Assume a folder error was set due to bad ignores on the latest scan.
Previously, doing a manual rescan would result in:
1. Clearing the folder error, which schedules (immediately) an fs
watcher restart
2. Attempting to load the ignores, which fails, so we set a folder
error and bail.
3. Now the fs watcher restarts, as scheduled, so we trigger a scan.
Goto 1.
This change fixes this by not clearing the error until the error is
actually cleared, that is, if both the health check and ignore loading
succeeds.
This introduces a better set of defaults for large databases. I've
experimentally determined that it results in much better throughput in a
couple of scenarios with large databases, but I can't give any
guarantees the values are always optimal. They're probably no worse than
the defaults though.
NATSymmetricUDPFirewall actually is not NAT at all, but means the machine has a global IP address and an UDP firewall in front (RFC calls it Symmetric UDP Firewall). This is punchable fine, both theoretically and also practically in testing.
* lib/model: Don't panic on failed chmod-back on directory (fixes#5836)
This makes the "in writable dir"-wrapper log chmod-back errors instead
of panicking. To do that we need a logger so the function moved into the
model package which is also the only place it's used. The tests came
along.
(The test also exercised osutil.RenameOrCopy like some sort of
piggybacking. I removed that.)
This adds a set of magical environment variables that can be used to
tweak the database parameters. It's totally undocumented and not
intended to be a long term or supported thing.
It's ugly, but there is a backstory. I have a couple of large
installations where the database options are inefficient or otherwise
suboptimal (24/7 compaction going on and stuff like that). I don't
*know* the correct database parameters, nor yet the formula or method to
derive them by, so this requires experimentation. Experimentation needs
to happen partly in production, and rolling out new builds for every
tweak isn't practical. This provides override points for all reasonable
values, while not changing anything by default.
Ideally, at the end of such experimentation, we'll know which values are
relevant to change and in what manner, and can provide a more user
friendly knob to do so - or do it automatically based on the database
size.
* add skeleton for lib/syncthing
* copy syncthingMain to lib/syncthing (verbatim)
* Remove code to deduplicate copies of syncthingMain
* fix simple build errors
* move stuff from main to syncthing with minimal mod
* merge runtime options
* actually use syncthing.App
* pass io.writer to lib/syncthing for auditing
* get rid of env stuff in lib/syncthing
* add .Error() and comments
* review: Remove fs interactions from lib
* and go 1.13 happened
* utility functions
Per the sync/atomic bug note:
> On ARM, x86-32, and 32-bit MIPS, it is the caller's
> responsibility to arrange for 64-bit alignment of 64-bit words
> accessed atomically. The first word in a variable or in an
> allocated struct, array, or slice can be relied upon to be
> 64-bit aligned.
All atomic accesses of 64-bit variables in syncthing code base are
currently ok (i.e they are all 64-bit aligned).
Generally, the bug is triggered because of incorrect alignement
of struct fields. Free variables (declared in a function) are
guaranteed to be 64-bit aligned by the Go compiler.
To ensure the code remains correct upon further addition/removal
of fields, which would change the currently correct alignment, I
added the following comment where required:
// atomic, must remain 64-bit aligned
See https://golang.org/pkg/sync/atomic/#pkg-note-BUG.
* lib/versioner: Add placeholder to provide the absolute file path to external commands
This commit adds support for a new placeholder, %FILE_PATH_FULL%, to the
command of the external versioner. The placeholder will be replaced by
the absolute path of the file that should be deleted.
* Revert "lib/versioner: Add placeholder to provide the absolute file path to external commands"
This reverts commit fb48962b947358e90a76e87a7794adb6057de476.
* lib/versioner: Replace all placeholders in external command (fixes#5849)
Before this commit, only these placeholders were replaced that span a
whole word, for example "%FOLDER_PATH%". Words that consisted of more
than one placeholder or additional characters, for example
"%FOLDER_PATH%/%FILE_PATH%", were left untouched.
* fixup! lib/versioner: Replace all placeholders in external command (fixes#5849)
* lib/ur: Implement crash (panic) reporting (fixes#959)
This implements a simple crash reporting method. It piggybacks on the
panic log files created by the monitor process, picking these up and
uploading them from the usage reporting routine.
A new config value points to the crash receiver base URL, which defaults
to "https://crash.syncthing.net/newcrash" (following the pattern of
"https://data.syncthing.net/newdata" for usage reports, but allowing us
to separate the service as required).
* lib/fs, lib/model: Add error channel to Watch to avoid panics (fixes#5697)
* forgot unsupported watch
* and more non(-standard)-unixy fixes
* and windows test
* review
* lib/api, lib/connections, gui: Show connection error for disconnected devices (fixes#3345)
This adds functionality in the connetions service to track the last
error per address. That is in turn exposed in the /rest/system/status
API method, as that is also where we already show the listener status
from the connection service.
The GUI uses this info where it lists addresses, showing errors (if any)
in red underneath each address.
I also slightly refactored the existing status method on the connection
service to have a better name and return typed information.
* ok
* review
* formatting
* review
The check in ClusterConfig() when iterating through announced devices
in a folder explicitly skips entries without a non-zero IndexID.
Therefore, the check for IndexID == 0 just below will never be true
and the intended cleanup of local index data will not happen.
Plainly remove that check to make the intended case distinction work.
* lib/protocol: Wait for reader/writer loops on close (fixes#4170)
* waitgroup
* lib/model: Don't hold lock while closing connection
* fix comments
* review (lock once, func argument) and naming
* lib/model: Send cluster config before releasing pmut
* reshuffle
* add model.connReady to track cluster-config status
* Corrected comments/strings
* do it in protocol
This constructs the map of hashes of zero blocks from constants instead
of calculating it at startup time. A new test verifies that the map is
correct.
* cmd/syncthing, lib/gui: Separate gui into own package (ref #4085)
* fix tests
* Don't use main as interface name (make old go happy)
* gui->api
* don't leak state via locations and use in-tree config
* let api (un-)subscribe to config
* interface naming and exporting
* lib/ur
* fix tests and lib/foldersummary
* shorter URVersion and ur debug fix
* review
* model.JsonCompletion(FolderCompletion) -> FolderCompletion.Map()
* rename debug facility https -> api
* folder summaries in model
* disassociate unrelated constants
* fix merge fail
* missing id assignement
* lib/tlsutil: Enable TLS 1.3 when available, on test builds (fixes#5065)
This enables TLS 1.3 negotiation on Go 1.12 by setting the GODEBUG
variable. For now, this just gets enabled on test versions (those with a
dash in the version number).
Users wishing to enable this on production builds can set GODEBUG
manually.
The string representation of connections now includes the TLS version
and cipher suite. This becomes part of the log output on connections.
That is, when talking to an old client:
Established secure connection .../TLS1.2-TLS_ECDHE_ECDSA_WITH_AES_128_GCM_SHA256
and now potentially:
Established secure connection .../TLS1.3-TLS_AES_128_GCM_SHA256
(The cipher suite was there previously in the log output, but not the
TLS version.)
I also added this info as a new Crypto() method on the connection, and
propagate this out to the API and GUI, where it can be seen in the
connection address hover (although with bad word wrapping sometimes).
* wip
* wip
Flush the batch when exceeding a certain size, instead of when reaching a number
of batched operations.
Move batch to lowlevel to be able to use it in NamespacedKV.
Increase the leveldb memory buffer from 4 to 16 MiB.
* cleanup Fatal in lib/config/config.go
* cleanup Fatal in lib/config/folderconfiguration.go
* cleanup Fatal in lib/model/model.go
* cleanup Fatal in cmd/syncthing/monitor.go
* cleanup Fatal in cmd/syncthing/main.go
* cleanup Fatal in lib/api
* remove Fatal methods from logger
* lowercase in errors.Wrap
* one less channel
I'm working through linter complaints, these are some fixes. Broad
categories:
1) Ignore errors where we can ignore errors: add "_ = ..." construct.
you can argue that this is annoying noise, but apart from silencing the
linter it *does* serve the purpose of highlighting that an error is
being ignored. I think this is OK, because the linter highlighted some
error cases I wasn't aware of (starting CPU profiles, for example).
2) Untyped constants where we though we had set the type.
3) A real bug where we ineffectually assigned to a shadowed err.
4) Some dead code removed.
There'll be more of these, because not all packages are fixed, but the
diff was already large enough.
This adds a folder option "CopyOwnershipFromParent" which, when set,
makes Syncthing attempt to retain the owner/group information when
syncing files. Specifically, at the finisher stage we look at the parent
dir to get owner/group and then attempt a Lchown call on the temp file.
For this to succeed Syncthing must be running with the appropriate
permissions. On Linux this is CAP_FOWNER, which can be granted by the
service manager on startup or set on the binary in the filesystem. Other
operating systems do other things, but often it's not required to run as
full "root". On Windows this patch does nothing - ownership works
differently there and is generally less of a deal, as permissions are
inherited as ACLs anyway.
There are unit tests on the Lchown functionality, which requires the
above permissions to run. There is also a unit test on the folder which
uses the fake filesystem and hence does not need special permissions.
To do so the BlockMap struct has been removed. It behaves like any other prefixed
part of the database, but was not integrated in the recent keyer refactor. Now
the database is only flushed when files are in a consistent state.
There was a problem in iterating the sequence index that could result
in missing updates. The issue is that while the index was (correctly)
iterated in a snapshot, the actual file infos were read dirty outside of
the snapshot. This fixes this by doing the reads inside the snapshot,
and also updates a couple of other places that did the same thing more
or less harmfully (I didn't investigate).
To avoid similar issues in the future I did some renaming of the
getFile* methods - the ones in a transaction are just getFile, while the
ones directly on the database are variants of getFileDirty to highlight
what's going on.
* lib/fs, lib/model: Improve filesystem operations during tests (fixes#5422)
Introduces MustFilesystem that panics on errors and should be used for operations
during testing which must never fail.
Create temporary directories outside of testdata.
* don't do a filesystem, just a wrapper around os for testing
* fix copyright
This avoids waiting until next ping and timeout until the connection is actually
closed both by notifying the peer of the disconnect and by immediately closing
the local end of the connection after that. As a nice side effect, info level
logging about dropped connections now have the actual reason in it, not a generic
timeout error which looks like a real problem with the connection.
* go mod init; rm -rf vendor
* tweak proto files and generation
* go mod vendor
* clean up build.go
* protobuf literals in tests
* downgrade gogo/protobuf
Here the event Logger is rewritten as a service with a main loop instead
of mutexes. This loop has a select with essentially two legs: incoming
events, and subscription changes. When both are possible select will
chose one randomly, thus ensuring that in practice unsubscribes will
happen timely and not block the system.
Updates the package and fixes a test that depended on the old behavior
of Write() being equivalent to Reset()+Write() which is no longer the
case. The scanner already did resets after each block write, so this is
fine.
This changes the TLS and certificate handling in a few ways:
- We always use TLS 1.2, both for sync connections (as previously) and
the GUI/REST/discovery stuff. This is a tightening of the requirements
on the GUI. AS far as I can tell from caniusethis.com every browser from
2013 and forward supports TLS 1.2, so I think we should be fine.
- We always greate ECDSA certificates. Previously we'd create
ECDSA-with-RSA certificates for sync connections and pure RSA
certificates for the web stuff. The new default is more modern and the
same everywhere. These certificates are OK in TLS 1.2.
- We use the Go CPU detection stuff to choose the cipher suites to use,
indirectly. The TLS package uses CPU capabilities probing to select
either AES-GCM (fast if we have AES-NI) or ChaCha20 (faster if we
don't). These CPU detection things aren't exported though, so the tlsutil
package now does a quick TLS handshake with itself as part of init().
If the chosen cipher suite was AES-GCM we prioritize that, otherwise we
prefer ChaCha20. Some might call this ugly. I think it's awesome.
In a recent change (#5201) this return disappeared. The effect is that
we first shortcut the file and then also treat it normally. This results
in to database updates after each other, which are bound to end up in
the same batch. This means we remove one sequence entry and add two.
Not marking the issues as fixed, because I need to do more testing and
there are other discrepancies...
This adds a thin type that holds the state associated with the
leveldb.DB, leaving the huge Instance type more or less stateless. Also
moves some keying stuff into the DB package so that other packages need
not know the keying specifics.
(This does not, yet, fix the cmd/stindex program, in order to keep the
diff size down. Hence the keying constants are still exported.)
* lib/model, cmd/syncthing: Wait for folder restarts to complete (fixes#5233)
This is the somewhat ugly - but on the other hand clear - fix for what
is really a somewhat thorny issue. To avoid zombie folder runners a new
mutex is introduced that protects the RestartFolder operation. I hate
adding more mutexes but the alternatives I can think of are worse.
The other part of it is that the POST /rest/system/config operation now
waits for the config commit to complete. The point of this is that until
the commit has completed we should not accept another config commit. If
we did, we could end up with two separate RestartFolders queued in the
background. While they are both correct, and will run without
interfering with each other, we can't guarantee the order in which they
will run. Thus it could happen that the newer config got committed
first, and the older config commited after that, leaving us with the
wrong config running.
* test
* wip
* hax
* hax
* unflake test
* per folder mutexes
* paranoia
* race
* lib/fs: Add fakefs
This adds a new fake filesystem type. It's described rather extensively
in fakefs.go, but the main point is that it's for testing: when you want
to spin up a Syncthing and have a terabyte or two of random files that
can be synced somewhere, or an inifitely large filesystem to sync files
into.
It has pseudorandom properties such that data read from one fakefs can
be written into another fakefs and read back and it will look
consistent, without any of the data actually being stored.
To use:
<folder id="default" path="whatever" ...>
<filesystemType>fake</filesystemType>
This will create an empty fake filesystem. You can also specify that it
should be prefilled with files:
<folder id="default" path="whatever?size=2000000" ...>
<filesystemType>fake</filesystemType>
This will create a filesystem filled with 2TB of random data that can be
scanned and synced. There are more options, see fakefs.go.
Prefilled data is based on a deterministic seed, so you can index the
data and restart Syncthing and the index is still correct for all the
stored data.
The problem here is that we would update the sequence index before
updating the FileInfos, which would result in a high sequence number
pointing to a low-sequence FileInfo. The index sender would pick up the
high sequence number, send the old file, and think everything was good.
On the receiving side the old file is a no-op and ignored. The file
remains out of sync until another update for it happens.
This fixes that by correcting the order of operations in the database
update: first we remove old sequence index entries, then we update the
FileInfos (which now don't have anything pointing to them) and then we
add the sequence indexes (which the index sender can see).
The other option is to add "proper" transactions where required at the
database layer. I actually have a branch for that, but it's literally
thousands of lines of diff and I'm putting that off for another day as
this solves the problem...
The problem here is that we would update the sequence index before
updating the FileInfos, which would result in a high sequence number
pointing to a low-sequence FileInfo. The index sender would pick up the
high sequence number, send the old file, and think everything was good.
On the receiving side the old file is a no-op and ignored. The file
remains out of sync until another update for it happens.
This fixes that by correcting the order of operations in the database
update: first we remove old sequence index entries, then we update the
FileInfos (which now don't have anything pointing to them) and then we
add the sequence indexes (which the index sender can see).
The other option is to add "proper" transactions where required at the
database layer. I actually have a branch for that, but it's literally
thousands of lines of diff and I'm putting that off for another day as
this solves the problem...
This removes the out of disk space check from CheckHealth. The disk space is now
only checked if there are files to pull, in which case pulling those files is
stopped, but everything else (dirs, links, deletes) keeps running -> can recover
disk space through pulling.
Adds a receive only folder type that does not send changes, and where the user can optionally revert local changes. Also changes some of the icons to make the three folder types distinguishable.
This is an improvement of PR #4493 and related to (and maybe fixing) #4961
and #4475. Maybe fixing, because there is no clear reproducer for that
problem.
The previous PR added a mechanism to resurrect missing parent directories,
if there is a valid child file to be pulled. The same mechanism does not
exist for dirs and symlinks, even though a missing parent can happen for
those items as well. Therefore this PR extends the resurrection to all types
of pulled items.
In addition I moved the IsDeleted branch while iterating over
processDirectly to the existing IsDeleted branch in the WithNeed iteration.
This saves one pointless assignment and IsDeleted query. Also
We have the invalid bit to indicate that a file isn't good. That's enough for remote devices. For ourselves, it would be good to know sometimes why the file isn't good - because it's an unsupported type, because it matches an ignore pattern, or because we detected the data is bad and we need to rescan it.
Or, and this is the main future reason for the PR, because it's a change detected on a receive only device. We will want something like the invalid flag for those changes, but marking them as invalid today means the scanner will rehash them. Hence something more fine grained is required.
This introduces a LocalFlags fields to the FileInfo where we can stash things that we care about locally. For example,
FlagLocalUnsupported = 1 << 0 // The kind is unsupported, e.g. symlinks on Windows
FlagLocalIgnored = 1 << 1 // Matches local ignore patterns
FlagLocalMustRescan = 1 << 2 // Doesn't match content on disk, must be rechecked fully
The LocalFlags fields isn't sent over the wire; instead the Invalid attribute is calculated based on the flags at index sending time. It's on the FileInfo anyway because that's what we serialize to database etc.
The actual Invalid flag should after this just be considered when building the global state and figuring out availability for remote devices. It is not used for local file index entries.
To optimize WithNeed, which is called for the local device whenever an index
update is received. No tracking for remote devices to conserve db space, as
WithNeed is only queried for completion.
I'm trying to slowly clean this up a bit, and moving functionality out
into the folder types and having those methods not reach into model is
part of it. That can mean takign some odd arguments in the meantime,
some of those should probably become interfaces or properties on folder
in the long term.
The functionality was anyway mostly implemented there and not isolated
in the folderScanner type. The attempt to refactor it out in the other
direction wouldn't work given that the event loop and stuff is on
`folder`.
This adds a couple of utilities for transporting databases in JSON and a
test to load a database and verify a couple of invalid bits. The test
itself is quite pointless at the moment, but it lays the groundwork for
testing the migration of this data in the next step (after the invalid
bit should be changed to local flags for local files).
When that happens we need to have a database in the old format already
there in order to be able to test the migration.
To newer names better reflecting their types and yet sorting together
with folder.go. Doing it now without asking because there are no open
PRs that will get killed by it, and to avoid bikeshedding the names.
The actual pull method (which is really the only thing that differs
between them) is now an interface member which gets overridden by the
subclass.
"Subclass?!" Well, this is dynamic dispatch with overriding, I guess.
Instead of walking and unmarshalling the entire db and sorting the resulting
file infos by sequence, add store device keys by sequence number in the
database. Thus only the required file infos need be unmarshalled and are already
sorted by index.
Bumping the limit to 2 * the max block size (16 MiB) is a slight
increase compared to previously. Nonetheless I think it's good to allow
us to queue one request and have one on the way in, or conversely have
one large block on the way in and be able to ask for smaller blocks from
others at the same time.
Two small behavior changes: don't "charge" the data to the global rate
limit until it's been accepted by the device specific limiter, and fix
the send/recv direction in the log print on per device rate limits.
clearAddresses write locks the struct and then calls notify. notify in turn tries to obtain a read lock on the same mutex. The result was a deadlock. This change unlocks the struct before calling notify.
Given that we've taken on the resposibility of maintaining this forked
package I've added it to the Syncthing organization. We still vendor it
like an external package, because it's convenient to keep it as a fork
of upstream to easier merge and file pull requests towards them.
When dropping delta index IDs due to upgrade, only drop our local one.
Previously, when dropping all of them, we would trigger a full send in
both directions on first connect after upgrade. Then the other side
would upgrade, doing the same thing. Net effect is full index data gets
sent twice in both directions.
With this change we just drop our local ID, meaning we will send our
full index on first connect after upgrade. When the other side upgrades,
they will do the same. This is a bit less cruel.
Unignored files are marked as conflicting while scanning, which is then resolved
in the subsequent pull. Automatically reconciles needed items on send-only
folders, if they do not actually differ except for internal metadata.
This doesn't happen today, but it might in the future if the block size
were increased or made variable and we were talking to a client from the
future.
* lib/db: Don't panic on negative counts (fixes#4659)
So, negative counts should never happen and hence the original idea to
panic. However, this sucks as the panic will happen in a folder runner,
be automatically swallowed by suture, and the runner gets restarted but
now we are in a bad state. (Related: #4758)
At the time of writing the global list is somewhat in flux (we've
changed how ignored files are handled, invalid bits, etc.) and I think
that can cause unusual conditions here. Hence just fixing up the numbers
instead until the next full recount.
When scanner.Walk detects a change, it now returns the new file info as well as the old file info. It also finds deleted and ignored files while scanning.
Also directory deletions are now always committed to db after their children to prevent temporary failure on remote due to non-empty directory.
This removes a number of timing related things, leaving just the total
test timeout now bumped to one minute. Normally we get the filesystem
events within a second or so, so this doesn't affect the test time in
the successfull case. If we don't actually get the events we expect
within a minute I think we are legitimately in "failed" territory.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4715
LGTM: imsodin, AudriusButkevicius
Since #4340 pulls aren't happening every 10s anymore and may be delayed up to 1h.
This means that no folder error event reaches the web UI for a long time, thus no
failed items will show up for a long time. Now errors are populated when the
web UI is opened.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4650
LGTM: AudriusButkevicius
It turns out that ZFS doesn't do any normalization when storing files,
but does do normalization "as part of any comparison process".
In practice, this seems to mean that if you LStat a normalized filename,
ZFS will return the FileInfo for the un-normalized version of that
filename.
This meant that our test to see whether a separate file with a
normalized version of the filename already exists was failing, as we
were detecting the same file.
The fix is to use os.SameFile, to see whether we're getting the same
FileInfo from the normalized and un-normalized versions of the same
filename.
One complication is that ZFS also seems to apply its magic to os.Rename,
meaning that we can't use it to rename an un-normalized file to its
normalized filename. Instead we have to move via a temporary object. If
the move to the temporary object fails, that's OK, we can skip it and
move on. If the move from the temporary object fails however, I'm not
sure of the best approach: the current one is to leave the temporary
file name as-is, and get Syncthing to syncronize it, so at least we
don't lose the file. I'm not sure if there are any implications of this
however.
As part of reworking normalizePath, I spotted that it appeared to be
returning the wrong thing: the doc and the surrounding code expecting it
to return the normalized filename, but it was returning the
un-normalized one. I fixed this, but it seems suspicious that, if the
previous behaviour was incorrect, noone ever ran afoul of it. Maybe all
filesystems will do some searching and give you a normalized filename if
you request an unnormalized one.
As part of this, I found that TestNormalization was broken: it was
passing, when in fact one of the files it should have verified was
present was missing. Maybe this was related to the above issue with
normalizePath's return value, I'm not sure. Fixed en route.
Kindly tested by @khinsen on the forum, and it appears to work.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4646
This adds one new feature, that discovery servers can have ?nolookup to
be used only for announces. The default set of discovery servers is
changed to:
- discovery.s.n used for lookups. This is dual stack load balanced over
all discovery servers, and returns both IPv4 and IPV6 results when they
exist.
- discovery-v4.s.n used for announces. This has IPv4 addresses only and
the discovery servers will update the unspecified address with the IPv4
source address, as usual.
- discovery-v6.s.n which is exactly the same for IPv6.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4647
This no longer pokes at model internals, and only touches the config.
As a result, model handles this in CommitConfiguration, which restarts
the folders if things change, which repopulate m.folderDevice, m.deviceFolder
and other interal mappings.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4639
These files always have the symlink bit set, because they are reparse
points. Nonetheless they are not symlinks, and Lstat reports a size for
them. We use this fact to disambiguate, and hope fervently that nothing
else matches this description so it comes back to bite us...
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4622
Just because there are a ton of people struggling to set env vars.
Perhaps this should live in advanced settings, and perhaps we should have a button to view the log.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4604
LGTM: calmh, imsodin
Also attempt to handle this nicer by ignoring the truncate failure when
it doesn't matter, and recover by deleting the temp file when it does.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4594
This keeps the data we need about sequence numbers and object counts
persistently in the database. The sizeTracker is expanded into a
metadataTracker than handled multiple folders, and the Counts struct is
made protobuf serializable. It gains a Sequence field to assist in
tracking that as well, and a collection of Counts become a CountsSet
(for serialization purposes).
The initial database scan is also a consistency check of the global
entries. This shouldn't strictly be necessary. Nonetheless I added a
created timestamp to the metadata and set a variable to compare against
that. When the time since the metadata creation is old enough, we drop
the metadata and rebuild from scratch like we used to, while also
consistency checking.
A new environment variable STCHECKDBEVERY can override this interval,
and for example be set to zero to force the check immediately.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4547
LGTM: imsodin
So STDEADLOCK seems to do the same thing as STDEADLOCKTIMEOUT, except in
the other package. Consolidate?
STDEADLOCKTHRESHOLD is actually called STLOCKTHRESHOLD, correct the help
text.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4598
Fix the folder restart behavior (ignore Label), improve the API for that
(imho).
Also removes the tab switch animation in the settings modal, because
annoying.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4577
This should address issue as described in https://forum.syncthing.net/t/stun-nig-party-with-paused-devices/10942/13
Essentially the model and the connection service goes out of sync in terms of thinking if we are connected or not.
Resort to model as being the ultimate source of truth.
I can't immediately pin down how this happens, yet some ideas.
ConfigSaved happens in separate routine, so it's possbile that we have some sort of device removed yet connection comes in parallel kind of thing.
However, in this case the connection exists in the model, and does not exist in the connection service and the only way for the connection to be removed
in the connection service is device removal from the config.
Given the subject, this might also be related to the device being paused.
Also, adds more info to the logs
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4533
We need to reset prevSeq so that we force a full check when someone
reconnects - the sequence number may not have changed due to the
reconnect. (This is a regression; we did this before f6ea2a7.)
Also add an optimization: we schedule a pull after scanning, but there
is no need to do so if no changes were detected. This matters now
because the scheduled pull actually traverses the database which is
expensive.
This, however, makes the pull not happen on initial scan if there were
no changes during the initial scan. Compensate by always scheduling a
pull after initial scan in the rwfolder itself.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4508
LGTM: imsodin, AudriusButkevicius
This is step one of a hundred fifty on the path to case insensitivity.
It brings in the basic case folding mechanism and adds it to the
mtimefs, as this is something outside the fileset that touches stuff in
the database based on name. No effort to convert or handle existing
entries when the insensitivity is changed, I don't think we need it...
Useless by itself but includes tests and will reduce the review load
along the way.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4521
This makes it OK to not have any listeners working. Specifically,
- We don't complain about an empty listener address
- We don't complain about not having anything to announce to global
discovery servers
- We don't send local discovery packets when there is nothing to
announce.
The last point also fixes a thing where the list of addresses for local
discovery was set at startup time and never refreshed.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4517
Well Tested(TM)
Introduces a potential issue where we always pick some connectable but dodgy connection that breaks
soon after the TLS handshake.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4489
Diff is large due to comment reformatting and indentation but all it
does is wrap the file mtime/size/permissions check in an "if
stat.IsRegular()".
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4507
This removes a significant, complex chunk of database code. The
"replace" operation walked both the old and new in lockstep and made the
relevant changes to make the new situation correct. But since delta
indexes we pretty much never need this - we just used replace to drop
the existing data and start over.
This makes that explicit and removes the complexity.
(This is one of those things that would be annoying to make case
insensitive, while the actual "drop and then insert" that we do is
easier.)
This is fairly well unit tested...
The one change to the tests is to cover the fact that previously replace
with something identical didn't bump the sequence number, while
obviously removing everything and re-inserting does. This is not
behavior we depend on anywhere.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4500
LGTM: imsodin, AudriusButkevicius
With VPNs and stuff we can get a single failure on an interface that
supposedly supports broadcasts without it being fatal.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4415
