Commit Graph

13 Commits

Author SHA1 Message Date
Aliaksandr Valialkin
e2de5bf763
lib/{storage,mergeset}: convert InitFromFilePart to MustInitFromFilePart
Callers of InitFromFilePart log the error and exit.
It is better to log the error with the path to the part and the call stack
directly inside the MustInitFromFilePart() function.
This simplifies the code at callers' side while leaving the same level of debuggability.
2023-04-14 15:47:20 -07:00
Aliaksandr Valialkin
aac3dccfd1
lib/fs: replace MkdirAllIfNotExist->MustMkdirIfNotExist and MkdirAllFailIfExist->MustMkdirFailIfExist
Callers of these functions log the returned error and then exit. The returned error already contains the path
to directory, which was failed to be created. So let's just log the error together with the call stack
inside these functions. This leaves the debuggability of the returned error at the same level
while allows simplifying the code at callers' side.

While at it, properly use MustMkdirFailIfExist instead of MustMkdirIfNotExist inside inmemoryPart.MustStoreToDisk().
It is expected that the inmemoryPart.MustStoreToDick() must fail if there is already a directory under the given path.
2023-04-13 22:22:08 -07:00
Aliaksandr Valialkin
b4c330ea2b
lib/fs: rename MustWriteFileAndSync to MustWriteSync in order to improve readability a bit
This is a follow-up for 2a8395be05
2023-04-13 22:20:31 -07:00
Aliaksandr Valialkin
1cda542c48
lib/fs: replace WriteFileAndSync with MustWriteAndSync
When WriteFileAndSync fails, then the caller eventually logs the error message
and exits. The error message returned by WriteFileAndSync already contains the path
to the file, which couldn't be created. This information alongside the call stack
is enough for debugging the issue. So just use log.Panicf("FATAL: ...") inside MustWriteAndSync().
This simplifies error handling at caller side a bit.
2023-04-13 22:17:34 -07:00
Aliaksandr Valialkin
eb7df27e20
lib/{mergeset,storage}: properly fsync part directory listing after writing in-memory part to disk
This is a follow-up after 42bba64aa7

Previously the part directory listing was fsync'ed implicitly inside partHeader.WriteMetadata()
by calling fs.WriteFileAtomically(). Now it must be fsync'ed explicitly.

There is no need in fsync'ing the parent directory, since it is fsync'ed by the caller
when updating parts.json file.
2023-04-13 21:21:46 -07:00
Aliaksandr Valialkin
f6c36d5dfd
lib/storage: consistently use OS-independent separator in file paths
This is needed for Windows support, which uses `\` instead of `/` as file separator

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/70
2023-03-25 14:34:36 -07:00
Aliaksandr Valialkin
fc3d826d7f
all: add Windows build for VictoriaMetrics
This commit changes background merge algorithm, so it becomes compatible with Windows file semantics.

The previous algorithm for background merge:

1. Merge source parts into a destination part inside tmp directory.
2. Create a file in txn directory with instructions on how to atomically
   swap source parts with the destination part.
3. Perform instructions from the file.
4. Delete the file with instructions.

This algorithm guarantees that either source parts or destination part
is visible in the partition after unclean shutdown at any step above,
since the remaining files with instructions is replayed on the next restart,
after that the remaining contents of the tmp directory is deleted.

Unfortunately this algorithm doesn't work under Windows because
it disallows removing and moving files, which are in use.

So the new algorithm for background merge has been implemented:

1. Merge source parts into a destination part inside the partition directory itself.
   E.g. now the partition directory may contain both complete and incomplete parts.
2. Atomically update the parts.json file with the new list of parts after the merge,
   e.g. remove the source parts from the list and add the destination part to the list
   before storing it to parts.json file.
3. Remove the source parts from disk when they are no longer used.

This algorithm guarantees that either source parts or destination part
is visible in the partition after unclean shutdown at any step above,
since incomplete partitions from step 1 or old source parts from step 3 are removed
on the next startup by inspecting parts.json file.

This algorithm should work under Windows, since it doesn't remove or move files in use.
This algorithm has also the following benefits:

- It should work better for NFS.
- It fits object storage semantics.

The new algorithm changes data storage format, so it is impossible to downgrade
to the previous versions of VictoriaMetrics after upgrading to this algorithm.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3236
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3821
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/70
2023-03-19 23:28:26 -07:00
Aliaksandr Valialkin
7d5c64eb7a
all: add -inmemoryDataFlushInterval command-line flag for controlling the frequency of saving in-memory data to disk
The main purpose of this command-line flag is to increase the lifetime of low-end flash storage
with the limited number of write operations it can perform. Such flash storage is usually
installed on Raspberry PI or similar appliances.

For example, `-inmemoryDataFlushInterval=1h` reduces the frequency of disk write operations
to up to once per hour if the ingested one-hour worth of data fits the limit for in-memory data.

The in-memory data is searchable in the same way as the data stored on disk.
VictoriaMetrics automatically flushes the in-memory data to disk on graceful shutdown via SIGINT signal.
The in-memory data is lost on unclean shutdown (hardware power loss, OOM crash, SIGKILL).

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3337
2022-12-05 15:28:09 -08:00
Aliaksandr Valialkin
7ffa66d249
lib/{mergeset,storage}: take into account byte slice capacity when returning the size of in-memory part
This results in more correct reporting of memory usage for in-memory parts
2022-12-03 22:31:34 -08:00
Aliaksandr Valialkin
b805a675f3 lib/{mergeset,storage}: switch from sync.Pool to chan-based pool for inmemoryPart objects
This should reduce memory usage on systems with big number of CPU cores,
since every inmemoryPart object occupies at least 64KB of memory and sync.Pool maintains
a separate pool inmemoryPart objects per each CPU core.

Though the new scheme for the pool worsens per-cpu cache locality, this should be amortized
by big sizes of inmemoryPart objects.
2021-07-06 16:33:25 +03:00
Aliaksandr Valialkin
3845420a8f lib: extract common code for returning fast unix timestamp into lib/fasttime 2020-05-14 23:06:50 +03:00
Aliaksandr Valialkin
41f512af1c all: add vm_data_size_bytes metrics for easy monitoring of on-disk data size and on-disk inverted index size 2019-07-04 19:43:04 +03:00
Aliaksandr Valialkin
1836c415e6 all: open-sourcing single-node version 2019-05-23 00:18:06 +03:00