Commit Graph

54 Commits

Author SHA1 Message Date
Jun Wu
d8bdae0449 indexedlog: remove chown feature
Summary:
We removed the feature in D20704618 and it does not cause complaints.
Let's remove the code supporting the chown feature.

Reviewed By: DurhamG

Differential Revision: D21170307

fbshipit-source-id: c845016219e8c681930bb1780b94e6d31ca99730
2020-04-27 15:47:59 -07:00
Jun Wu
6bddc1df08 rotatelog: avoid loading broken Logs multiple times
Summary:
RotateLog loads older logs lazily. If an older log is broken, remember that and avoid
loading the broken log again.

Reviewed By: DurhamG

Differential Revision: D20663899

fbshipit-source-id: 7a4b5279cc6387c19329a51048bfe1be2e0bc1f8
2020-03-30 11:34:49 -07:00
Xavier Deguillard
8c1f033f50 indexedlog: address clippy warnings
Summary:
These were from a wide variety of warnings. The only one I haven't addressed is
that clippy complains that Pin<Box<Vec<u8>>> can be replaced by Pin<Vec<u8>>. I
haven't investigated too much into it, someone more familiar with this code can
probably figure out if this is buggy or not :)

Reviewed By: DurhamG

Differential Revision: D20469647

fbshipit-source-id: d42891d95c1d21b625230234994ab49bbc45b961
2020-03-18 10:16:38 -07:00
Jun Wu
8115053c00 indexedlog: implement xxd-like fmt::Debug for Log
Summary: This makes `hg debugindexedlog dump` more useful.

Reviewed By: sfilipco

Differential Revision: D20448863

fbshipit-source-id: c5cc24449ae00ee329ce02bf0adf947ff57e72ed
2020-03-16 10:21:46 -07:00
Jun Wu
97e9b81ba5 indexedlog: remove compiler warnings on Windows
Summary:
Some `use`s are not used on Windows. The code was also formatted using the
latest rustfmt.

Reviewed By: xavierd

Differential Revision: D20379704

fbshipit-source-id: ffadcd68e4e0440dcbd2a4e1ad8532b47a9d83e2
2020-03-11 15:54:19 -07:00
Jun Wu
009ea22175 indexedlog: retry rename in atomic_write on Windows
Summary:
Recently there are some Windows-related test flakiness in . All of them are
caused by `file.persist(path)` in `atomic_write_plain` failing with
"Access Denied". Since that can be caused by Windows Anti-Virus scans or other
weird stuff, let's workaround around it using automatically retires.

Process Explorer does not provide extra information:

    indexedlog-d0c6135fd7ed9ece.exe	5868	SetRenameInformationFile	C:\Users\quark\AppData\Local\Temp\.tmpKERc5G\.tmpcfDsQQ	ACCESS DENIED	ReplaceIfExists: True, FileName: C:\Users\quark\AppData\Local\Temp\.tmpKERc5G\meta

A successful rename looks like:

    indexedlog-d0c6135fd7ed9ece.exe	5868	SetRenameInformationFile	C:\Users\quark\AppData\Local\Temp\.tmpKERc5G\.tmpbXEVw0	SUCCESS	ReplaceIfExists: True, FileName: C:\Users\quark\AppData\Local\Temp\.tmpKERc5G\meta

Reviewed By: ikostia

Differential Revision: D20379618

fbshipit-source-id: db3e6be3d785875486f7a517df11cbf58bf65ddd
2020-03-11 10:06:47 -07:00
Jun Wu
5f84fc8222 indexedlog: use dev-logger
Summary: This makes `RUST_LOG` work for indexedlog tests.

Reviewed By: xavierd

Differential Revision: D20286515

fbshipit-source-id: ff4a1476eb01a9067dabe3622fd598f65fe86a18
2020-03-10 14:16:39 -07:00
Jun Wu
cf72dc45f5 indexedlog: add some tracing information
Summary: Those has helped me debugging some issues.

Reviewed By: xavierd

Differential Revision: D20286513

fbshipit-source-id: 012ddb16c2d0efd8f8697a5ecd4564ea31d65630
2020-03-10 14:16:38 -07:00
Jun Wu
3103fcf62b indexedlog: reload content after obtaining a lock at open time
Summary:
The old code does "read, lock, write", which is unsound because after "lock"
the data just read can be outdated and needs a reload.

Reviewed By: xavierd

Differential Revision: D20306137

fbshipit-source-id: a1c29d5078b2d47ee95cf00db8c1fcbe3447cccf
2020-03-06 08:12:02 -08:00
Jun Wu
75e4ffc17f indexedlog: change IndexDef.lag_threshold back from entries to bytes
Summary:
I thought the index function could be the bottleneck. However, the Log reading
(xxhash, decoding vlqs) can be much slower for very long entries. Therefore
using bytes as the lag threshold is better. It does leaked the Log
implementation details (how it encodes an entry) to some extend, though.

Reverts D20042045 and D20043116 logically. The lagging calculation is using
the new Index::get_original_meta API, which is easier to verify correctness
(In fact, it seems the old code is wrong - it might skip Index flushes if
sync() is called multiple times without flushing).

This should mitigate an issue where a huge entry (generated by `hg trace`) in
blackbox does not get indexed in time and cause performance regressions.

Reviewed By: DurhamG

Differential Revision: D20286508

fbshipit-source-id: 7cd694b58b95537490047fb1834c16b30d102f18
2020-03-05 13:29:48 -08:00
Jun Wu
efff6f3592 indexedlog: add an API to get the Index meta that is not dirty
Summary: This will be used to more reliably detect index lags.

Reviewed By: DurhamG

Differential Revision: D20286518

fbshipit-source-id: c553b6587363a55603b75df12580588e3100e35f
2020-03-05 13:29:47 -08:00
Jun Wu
66e60bacb9 rotatelog: build indexes for older logs on access
Summary:
This ensures indexes are complete even if index format or definition has been
changed.

Reviewed By: DurhamG

Differential Revision: D20286509

fbshipit-source-id: fcc4ebc616a4501e4b6fd2f1a9826f54f40b99b8
2020-03-05 13:29:47 -08:00
Jun Wu
1c6310b9d6 rotatelog: add iter_dirty() API
Summary: This API has the benefit that it does not trigger loading older logs.

Reviewed By: DurhamG

Differential Revision: D20286512

fbshipit-source-id: 426421691ad1130cdbb2305612d76f18c9f8798c
2020-03-05 13:29:46 -08:00
Jun Wu
0ae5a59e9e indexedlog: fix metadata-only updates for Indexes
Summary:
Previously, `flush()` will skip writing the file if there are only metadata
changes. Fix it by detecting metadata changes.

This can potentially fix an issue that certain blackbox indexes are empty,
lagging and require scanning the whole log again and again. In that case,
the index itself is not changed (the root radix entry is not changed), but
only the metadata tracking how many bytes in Log the index covered
changed.

Reviewed By: sfilipco

Differential Revision: D20264627

fbshipit-source-id: 7ee48454a92b5786b847d8b1d738cc38183f7a32
2020-03-04 15:59:12 -08:00
Jun Wu
49464342fd indexedlog: try to use symlink for atomic_write on unix
Summary:
The change is in theory not necessary. However it improves the reliability on
OS crashes a bit, and can potentially workaround some bugs in filesystems
(as we saw in production where the atomic-written files are empty and the
system didn't crash).

The idea is, the `symlink` syscall does the file creation and "content" writing
together, while there is no way to create a file and write specific content
in one syscall. Note that the C symlink call uses 0-terminated string, and
the Rust stdlib exports it as accepting `Path`. To be safe, we encode binary
or non-utf8 content using `hex`.

For downgrade safety, the write path does not use symlink by default unless
format.use-symlink-atomic-write is set to true. This makes downgrade possible:
the read path is rolled out first, then we can turn on and off the write path.

The indexedlog Rust unit tests and test-doctor.t are migrated to use the new
symlink code paths.

Reviewed By: DurhamG

Differential Revision: D20153864

fbshipit-source-id: c31bd4287a8d29575180fbcf7227d2b04c4c1252
2020-03-04 07:23:48 -08:00
Jun Wu
def12896db indexedlog: add a utility function to read files crated by atomic_write
Summary:
This makes it possible to implement atomic_write differently (ex. use a
symlink).

Reviewed By: DurhamG

Differential Revision: D20153865

fbshipit-source-id: 07fa78c2f2dac696668f477c75f65cf70950b73f
2020-03-04 07:23:47 -08:00
Jun Wu
7c5e47bab1 indexedlog: rename chunk_size_log to chunk_size_logarithm
Summary:
This makes it clear that `log` is a math concept, not an append-only file like
`Log`.

Reviewed By: DurhamG

Differential Revision: D20149376

fbshipit-source-id: 67d2e9584b15f48759ca9b6dfce4279a5b1365a0
2020-03-03 13:41:28 -08:00
Jun Wu
1962fd5f5b indexedlog: update lagging indexes at open time
Summary:
Previously indexes are only updated at `sync()` time. This diff makes it so
`open()` can also update lagging indexes. This should make index migration
(ex. D19851355) smoother - indexes are built in time and users suffer less from
the absent of indexes.

Reviewed By: DurhamG

Differential Revision: D20042046

fbshipit-source-id: 20412661a0ca4f5f67b671137c47b6373a42981d
2020-02-28 09:23:58 -08:00
Jun Wu
6da3bdadd2 indexedlog: extract logic writing indexes to disk to a method
Summary: The logic is currently only used by `sync()`. I'd like to reuse it at `open()`.

Reviewed By: DurhamG

Differential Revision: D20042044

fbshipit-source-id: 5c9734ff68bdcf8f8c8710c6a821b18d3afeaca0
2020-02-28 09:23:58 -08:00
Jun Wu
afb24f8a8a indexedlog: change IndexDef.lag_threshold from bytes to entries
Summary:
This is more friendly for indexedlog users - deciding lag_threshold by number
of entries is easier than by bytes.

Initially, I thought checking `bytes` is cheaper and checking `entries` is more
expensive. However, practically we will have to build indexes for `entires`
anyway. So we do know the number of entries lagging behind.

Reviewed By: DurhamG

Differential Revision: D20042045

fbshipit-source-id: 73042e406bd8b262d5ef9875e45a3fd5f29f78cf
2020-02-28 09:23:58 -08:00
Jun Wu
55363a78a7 indexedlog: add API to convert &[u8] to zero-copy Bytes
Summary:
This can be useful for users of indexedlog when they want `Bytes` (to get rid
of the lifetime parameter).

This might be useful for storage layer that wants to take the ownership of the
returned bytes.

Reviewed By: xavierd

Differential Revision: D19818714

fbshipit-source-id: cb2d4e7deff921915e07454fee15cb94a3d5c00d
2020-02-28 09:23:57 -08:00
Jun Wu
556850e715 indexedlog: remove unused mmap utility functions
Summary: Those utilities are no longer necessary since the new code uses Bytes.

Reviewed By: xavierd

Differential Revision: D19818717

fbshipit-source-id: 0b43af0f1eae1a4288e84d4170db058b27f80334
2020-02-28 09:23:57 -08:00
Jun Wu
aaf59c569d indexedlog: replace Mmap with Bytes in Log
Summary: This simplifies the code a bit and makes it cheaper to clone the Log.

Reviewed By: xavierd

Differential Revision: D19818716

fbshipit-source-id: bbf07b8b36009d53b63d8066ec422fc3c3796840
2020-02-28 09:23:57 -08:00
Jun Wu
90ee3cb05a indexedlog: remove ChecksumTable
Summary: It's no longer used since Index now has inlined its checksum logic.

Reviewed By: ikostia

Differential Revision: D19850744

fbshipit-source-id: eb134e4c1613573a2d238710b44ad8119c80a5ee
2020-02-28 09:23:56 -08:00
Jun Wu
a1601bfdd9 indexedlog: bump index filename
Summary:
Change index filename and metadata name. This makes sure the new format and old
format are separate so upgrading or downgrading won't have issues.

Reviewed By: DurhamG

Differential Revision: D19851355

fbshipit-source-id: 25dee018073a90040f5818b32b753a3f589c10e0
2020-02-28 09:23:56 -08:00
Jun Wu
6f4bf325d5 indexedlog: write Checksum inline with Log
Summary:
Enhance the index format: The Root entry can be followed by an optional
Checksum entry which replaces the need of ChecksumTable.

The format is backwards compatible since the old format will be just
treated as "there is no ChecksumTable", and the ChecksumTable will be built on
the next "flush".

This change is non-trivial. But the tests are pretty strong - the bitflip test
alone covered a lot of issues, and the dump of Index content helps a lot too.

For the index itself without ".sum", checksum, this change is bi-directional
compatible:
1. New code reading old file will just think the old file does not have the
   checksum entry, similar to new code having checksum disabled.
2. Old code will think the root+checksum slice is the "root" entry. Parsing
   the root entry is fine since it does not complain about unknown data at the
   end.

However, this change dropped the logic updating ".sum" files. That part is an
issue blocking old clients from reading new data.

Reviewed By: DurhamG

Differential Revision: D19850741

fbshipit-source-id: 551a45cd5422f1fb4c5b08e3b207a2ffe3d93dea
2020-02-28 09:23:55 -08:00
Jun Wu
b9e3046a8d indexedlog: add Checksum entry to Index
Summary:
To solve the soundness issue of ChecksumTable raised by the last diff.
I plan to move Checksum logic to Index. This has multiple benefits:
- Solve the soundness issue of ChecksumTable.
- Indexedlog no longer writes the ".sum" files. `atomic_write` can be quite
  slow (tens of milliseconds) on Windows. So this should help perf - with
  many indexes, it can save hundreds of milliseconds on Windows per
  indexedlog sync.

This diff adds the definition and serialization of the new Checksum entry.
The index format is not updated yet.

Reviewed By: markbt

Differential Revision: D19850742

fbshipit-source-id: df6e6ed12a12ef0d2a782dc9d6b4dc5dec3f4b46
2020-02-28 09:23:55 -08:00
Jun Wu
0f09413ed4 indexedlog: add a broken test showing checksum_table is racy
Summary:
With the last change, mmap cost is reduced, but ChecksumTable is unsound in a
corner case: the buffer to check is shorter than what ChecksumTable covers:

    checksum:  |----chunk----|----chunk----|----chunk--|
    buf:       |-------------------------------|       |
                                               ^       ^
                                        logic len     physical len

The checksum table will be unable to verify the last chunk, since it does not
have enough data in buf.

The issues is exposed by stress testing the multithread sync tests. It's not
always easy to reproduce, though.

Reviewed By: markbt

Differential Revision: D19850745

fbshipit-source-id: a1a96080163b7b9b56dcd6c1673d5d8d10e18a2b
2020-02-28 09:23:55 -08:00
Jun Wu
1e10527482 indexedlog: share Bytes between Index and ChecksumTable
Summary: This avoids some extra mmap syscalls by ChecksumTable.

Reviewed By: xavierd

Differential Revision: D19818721

fbshipit-source-id: dace55193f2b4b0f35e3868781faa2d2998d3b58
2020-02-28 09:23:54 -08:00
Jun Wu
1ece621c4d indexedlog: replace Mmap with Bytes in Index
Summary:
This simplifies the code a bit (no special cases about 0-sized mmap buffers)
and makes it cheaper to clone the index buffer (just an Arc::clone, without
another mmap syscall).

Reviewed By: xavierd

Differential Revision: D19818718

fbshipit-source-id: e96d42af74c7f0bb11703c5da31cdfbd5d76c372
2020-02-28 09:23:54 -08:00
Jun Wu
03baa31789 indexedlog: switch from bytes to minibytes
Summary:
This makes it possible to use `Bytes` for mmap buffers.

The changes are because `minibytes::Bytes` does not implement `From<&[u8]>`
with the intention to make slice copy explicit.

Reviewed By: xavierd

Differential Revision: D19818719

fbshipit-source-id: c34ee451bfd2dc7bcbbcebd52a76444b6c236849
2020-02-12 13:57:37 -08:00
Jun Wu
907aadcdd7 indexedlog: add MultiLog
Summary: The MultiLog holds multiple Logs and can atomically sync them.

Reviewed By: DurhamG

Differential Revision: D19432659

fbshipit-source-id: 6ac7dc6f74468f985c6a6b0c419e888722a80037
2020-01-17 21:49:57 -08:00
Jun Wu
5aa872599c indexedlog: make ScopedDirLock remember which directory gets locked
Summary: This makes it possible to do extra sanity checks.

Reviewed By: DurhamG

Differential Revision: D19443783

fbshipit-source-id: 254c2537a6aadd25a67c5e48a768187ce65aa686
2020-01-17 21:49:56 -08:00
Jun Wu
2c9a3b9c61 indexedlog: use a method to create LogMetadata
Summary: This makes the code overall shorter.

Reviewed By: DurhamG

Differential Revision: D19443552

fbshipit-source-id: abd1db227830a88549c7eca1cfd08b67c4914518
2020-01-17 21:49:56 -08:00
Jun Wu
733961456f indexedlog: fix try_clone external key buffer handling
Summary:
In both cases (clone with or without dirty content), the external key buffers
used by indexes should be re-created, since mem_buf location has changed.

Reviewed By: DurhamG

Differential Revision: D19432657

fbshipit-source-id: fe6f76e7ccfd16ccd2f5c1d89866687a3503603e
2020-01-17 03:58:00 -08:00
Jun Wu
85d7253edd indexedlog: add "shared metadata" abstraction
Summary: This allows us to build the multi-log structure.

Reviewed By: DurhamG

Differential Revision: D19431786

fbshipit-source-id: e0e09b0d5a73d293a80626924b74ddf2ce6d6fa3
2020-01-17 03:57:59 -08:00
Jun Wu
36e70264b6 indexedlog: avoid log::OpenOptions::create_in_memory
Summary: Migrate to the new API. This is more compatible with the next change.

Reviewed By: DurhamG

Differential Revision: D19431788

fbshipit-source-id: dba1a88fd003d17fc1774b0cec9157d32c5acdb0
2020-01-17 03:57:59 -08:00
Jun Wu
de5772cb30 indexedlog: replace Log's dir with a new GenericPath type
Summary:
This allows us to incrementally abstract away parts related to filesystem from
Log. For example, instead of using std::fs to access filesystem directly, use
methods on the GenericPath instead.

Right now the main motivation is to add support for "multi-logs" sharing a single meta
file. To do that, methods reading and writing metas are moved to the
GenericPath type.

This also unifies the open functions. Now OpenOptions::create_in_memory can be
private. Empty in-memory Logs can be opened via `open(())`.

Reviewed By: DurhamG

Differential Revision: D19431784

fbshipit-source-id: dbdf94f60261e09f131c6fdd9fe3b99242a28af5
2020-01-17 03:57:59 -08:00
Jun Wu
bf133b797e indexedlog: expose io::ErrorKind in the wrapped error type
Summary: This makes an upcoming change easier.

Reviewed By: DurhamG

Differential Revision: D19432656

fbshipit-source-id: 65adc883c3c3937aa7022196b83c75715b820721
2020-01-17 03:57:58 -08:00
Jun Wu
24393faaeb indexedlog: move log::tests to a separate file
Summary: The goal is to split log.rs to smaller modules so it's easier to reason about.

Reviewed By: DurhamG

Differential Revision: D19431787

fbshipit-source-id: 23b8346c461da322e7a2240b8224e6194867aaee
2020-01-17 03:57:58 -08:00
Jun Wu
38db4b5cdc indexedlog: move log::OpenOptions to standalone modules
Summary:
The goal is to split log.rs to smaller modules so it's easier to reason about.

OpenOptions has many dependencies. Move the most complicated one (repair) to
another standalone module.

Reviewed By: DurhamG

Differential Revision: D19431783

fbshipit-source-id: 28c3af7cd6e19588bfe9c395e2648244faf3179d
2020-01-17 03:57:58 -08:00
Jun Wu
f6d3fd3d39 indexedlog: move log::LogMetaData to a standalone module
Summary: The goal is to split log.rs to smaller modules so it's easier to reason about.

Reviewed By: DurhamG

Differential Revision: D19431785

fbshipit-source-id: b9a598b3018267ff6e43ef57dc807cb4e880467c
2020-01-17 03:57:57 -08:00
Jun Wu
459ae48cef indexedlog: stabilize log::tests::test_repair_and_delete_content
Summary:
Previously, between 100 to 500 runs, the test is likely to fail:

  ---- log::tests::test_repair_and_delete_content stdout ----
  thread 'log::tests::test_repair_and_delete_content' panicked at 'assertion failed: `(left == right)`
    left: `"Verified first 141 entries, 999 of 1400012 bytes in log\nReset log size to 999\nIndex \"c\" is incompatible with (truncated) log\nRebuilt index \"c\""`,
   right: `"Rebuilt metadata\nVerified first 141 entries, 999 of 1400012 bytes in log\nReset log size to 999\nRebuilt index \"c\""`', src/log.rs:3414:9

The "Rebuilt metadata" part is missing.

This is because after D17742003, the end of `meta` is the `epoch`, which is a
random number. The test is rewriting the end of `meta` to corrupt it. That
has a chance to not corrupt the file. Change the test to corrupt the fixed
header of meta so it can always corrupt the file and therefore stabilize
the test.

Reviewed By: xavierd

Differential Revision: D19325087

fbshipit-source-id: 53d46c8a6cb9771582f8f37e27f185d303fde0ce
2020-01-09 08:48:47 -08:00
Jun Wu
2b4095e3fb indexedlog: fix warnings on Windows
Summary: Those warnings are not seen on POSIX build.

Reviewed By: sfilipco

Differential Revision: D19320441

fbshipit-source-id: feddf728eb9627834559b87d83e20f0afd9080c8
2020-01-08 18:11:38 -08:00
Jun Wu
cfe135737b indexedlog: fix clippy issues
Summary: Fix issues reported by clippy.

Reviewed By: sfilipco

Differential Revision: D19320121

fbshipit-source-id: 58f6402eb2a4f52914a760299bdfa72e5a63b2e6
2020-01-08 18:11:37 -08:00
Jun Wu
784da69352 indexedlog: support efficient index deletion by prefix
Summary:
The index can delete all keys matching a prefix more efficiently than deleting
them one by one. Expose this feature.

The `dag` crate will use this feature to delete all "non-master" segments and
ids efficiently.

Reviewed By: sfilipco

Differential Revision: D18825296

fbshipit-source-id: b8531695609238a16913254af61004170f12954e
2019-12-22 11:27:31 -08:00
Jun Wu
e51daf1fb1 indexedlog: expose Index::remove in log::IndexOutput
Summary: This makes it possible to define an index function that can delete data.

Reviewed By: sfilipco

Differential Revision: D18825299

fbshipit-source-id: 4eb03a001683092d99b439c8efb8e7909f543c70
2019-12-22 11:27:31 -08:00
Jun Wu
177360c0b5 indexedlog: implement Index::remove
Summary:
This makes it possible to actually delete keys from the index, which can be
handy for certain use-cases. For example, `dag` wants to rewrite non-master
ids and segments in certain cases.

Reviewed By: sfilipco

Differential Revision: D18825298

fbshipit-source-id: 3b69ca5fc763ba0c57bd16a28a349f2f829a0759
2019-12-22 11:27:31 -08:00
Jun Wu
343f79cf37 indexedlog: move parameters of index.insert_advanced to a structure
Summary:
This just moves parameters to a structure without changing the actual logic.
This is to make it possible to add a "remove" API to index.

Some variables are prefixed with `old_` or `new_` to make the code more
consistent.

Reviewed By: sfilipco

Differential Revision: D18825297

fbshipit-source-id: 27bd8438e66125c906ebf2044d6ff978b99c5986
2019-12-22 11:27:30 -08:00
Jun Wu
b8c04b5a97 indexedlog: do not repair non-existent directory
Summary: Otherwise the repair will fail with "unable to lock directory" errors.

Reviewed By: xavierd

Differential Revision: D18737911

fbshipit-source-id: 2c47b5b9a071e0db2d20fc385ef466aef1e732f6
2019-12-06 19:35:06 -08:00