Previously only logs inside the selected time range could be returned by stream_context pipe.
For example, the following query could return up to 10 surrounding logs only for the last 5 minutes,
while most users expect this query should return up to 10 surrounding logs without restrictions on the time range.
_time:5m panic | stream_context before 10
This enables the ability to implement stream context feature at VictoriaLogs web UI: https://github.com/VictoriaMetrics/VictoriaMetrics/issues/7063 .
Reduce memory usage when returning stream context over big log streams with millions of entries.
The new logic scans over all the log messages for the selected log stream, while keeping in memory only
the given number of surrounding logs. Previously all the logs for the given log stream on the selected time range
were loaded in memory before selecting the needed surrounding logs.
This should help https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6730 .
Reduce the scan performance for big log streams by fetching only the requested fields. For example, the following
query should be executed much faster than before if logs contain many fields other than _stream, _msg and _time:
panic | stream_context after 30 | fields _stream, _msg, _time
The set of log fields in the found logs may differ from the set of log fields present in the log stream.
So compare only the log fields in the found logs when searching for the matching log entry in the log stream.
While at it, return _stream field in the delimiter log entry, since this field is used by VictoriaLogs Web UI
for grouping logs by log streams.
- Consistently return the first `limit` log entries if the total size of found log entries doesn't exceed 1Mb.
See app/vlselect/logsql/sort_writer.go . Previously random log entries could be returned with each request.
- Document the change at docs/VictoriaLogs/CHANGELOG.md
- Document the `limit` query arg at docs/VictoriaLogs/querying/README.md
- Make the change less intrusive.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5674
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/5778
- Compare the actual free disk space to the value provided via -storage.minFreeDiskSpaceBytes
directly inside the Storage.IsReadOnly(). This should work fast in most cases.
This simplifies the logic at lib/storage.
- Do not take into account -storage.minFreeDiskSpaceBytes during background merges, since
it results in uncontrolled growth of small parts when the free disk space approaches -storage.minFreeDiskSpaceBytes.
The background merge logic uses another mechanism for determining whether there is enough
disk space for the merge - it reserves the needed disk space before the merge
and releases it after the merge. This prevents from out of disk space errors during background merge.
- Properly handle corner cases for flushing in-memory data to disk when the storage
enters read-only mode. This is better than losing the in-memory data.
- Return back Storage.MustAddRows() instead of Storage.AddRows(),
since the only case when AddRows() can return error is when the storage is in read-only mode.
This case must be handled by the caller by calling Storage.IsReadOnly()
before adding rows to the storage.
This simplifies the code a bit, since the caller of Storage.MustAddRows() shouldn't handle
errors returned by Storage.AddRows().
- Properly store parsed logs to Storage if parts of the request contain invalid log lines.
Previously the parsed logs could be lost in this case.
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4737
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/pull/4945
* lib/logstorage: switch to read-only mode when running out of disk space
Added support of `--storage.minFreeDiskSpaceBytes` command-line flag to allow graceful handling of running out of disk space at `--storageDataPath`.
See: https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4737
Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>
* lib/logstorage: fix error handling logic during merge
Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>
* lib/logstorage: fix log level
Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>
---------
Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>
Co-authored-by: Nikolay <nik@victoriametrics.com>
