VictoriaMetrics/app/vmselect
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
..
bufferedwriter lib/netutil: move IsTrivialNetworkError() function there, since it is used in multiple places across the code 2023-01-27 13:24:44 -08:00
clusternative lib/vmselectapi: limit the number of concurrently executed requests 2023-01-06 18:39:46 -08:00
deployment Rootless docker images by default (#358) 2020-03-27 21:18:32 +02:00
graphite all: use metricsql.CompileRegexp instead of regexp.Compile for compiling regexps used in graphite queries 2023-01-09 21:45:34 -08:00
graphiteql app,lib: fix typos in comments (#3804) 2023-02-13 09:32:35 -08:00
multiarch all: run apk update && apk upgrade in base Alpine Docker image in order to get all the recent security fixes 2023-02-09 14:03:02 -08:00
netstorage app/vmselect/netstorage: do not intern string representation of MetricName for time series received from vmstorage 2023-03-12 00:44:08 -08:00
prometheus app/vmselect: remove data race on updating EvalConfig.IsPartialResponse from concurrently running goroutines 2023-03-12 16:53:03 -07:00
promql app/vmselect/promql: add test to ensure 8-byte alignment (#3948) 2023-03-16 22:07:13 -07:00
querystats app/vmselect: do not track queries with less than 1ms execution time at /api/v1/status/top_queries 2021-07-15 16:53:35 +03:00
searchutils chore: Use http constants to replace numbers (#3846) 2023-02-22 18:59:32 -08:00
static/css app/vmselect: properly serve static css for /select/.../metric-relabel-debug page 2022-12-10 03:04:43 -08:00
vmui app/vmselect/vmui: make vmui-update after 00a0816ab1 2023-03-12 17:22:28 -07:00
main.go all: follow-up for 7a3e16e774 2023-03-08 01:42:58 -08:00
Makefile all: add Windows build for VictoriaMetrics 2023-03-19 23:28:26 -07:00
README.md app/vmselect: expose vmui at /vmselect/<accountID>/vmui/ instead of /vmselect/<accountID>/prometheus/vmui/ 2021-07-10 12:32:21 +03:00
vmui.go app/vmselect: follow-up after 820312a2b1 2023-01-11 23:37:51 -08:00

vmselect performs the following tasks:

  • Splits incoming selects to tasks for vmstorage nodes and issues these tasks to all the vmstorage nodes in the cluster.

  • Merges responses from all the vmstorage nodes and returns a single response.

The vmui directory contains static contents built from app/vmui package with make vmui-update command. The vmui page is available at http://<vmselect>:8481/select/<accountID>/vmui/.