Commit graph

18 commits

Author SHA1 Message Date
Aliaksandr Valialkin
dba0553e11
lib/cgroup: round GOMAXPROCS to the lower integer value of cpuQuota
Rounding GOMAXPROCS to the upper interger value of cpuQuota increases chances of CPU starvation,
non-optimimal goroutine scheduling and additional CPU overhead related to context switching.

So it is better to round GOMAXPROCS to the lower integer value of cpuQuota.
2024-09-23 16:11:59 +02:00
Aliaksandr Valialkin
f222cf9200
lib/cgroup: remove SetGOGC() function
GOGC can be already set via environment variable. There is no need in adding
new approaches for setting the GOGC (such as command-line flag), since they complicate operations.
2024-02-05 12:13:08 +02:00
Aliaksandr Valialkin
d01f0a89db
lib/cgroup: add SetGOGC() function
This function is going to be used by VictoriaLogs
2023-07-06 17:24:31 -07:00
Aliaksandr Valialkin
06f6de6d47
all: use os.{Read|Write}File instead of ioutil.{Read|Write}File
The ioutil.{Read|Write}File is deprecated since Go1.16 -
see https://tip.golang.org/doc/go1.16#ioutil

VictoriaMetrics needs at least Go1.18, so it is safe to remove ioutil usage
from source code.

This is a follow-up for 02ca2342ab
2022-08-21 23:55:20 +03:00
Aliaksandr Valialkin
f526c7814e
lib/cgroup: reduce the default GOGC value from 50% to 30%
This reduces memory usage under production workloads by up to 10%,
while CPU spent on GC remains roughly the same.

The CPU spent on GC can be monitored with go_memstats_gc_cpu_fraction metric
2022-04-06 14:00:50 +03:00
Aliaksandr Valialkin
a02dde6cc7
lib/cgroup: fall back to runtime.NumCPU() when determining process_cpu_cores_available metric if it is impossible to determine cpu quota via cgroups
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2107
2022-01-31 20:31:12 +02:00
Aliaksandr Valialkin
566e12874d
lib/cgroup: expose process_cpu_cores_available metric
This metric shows the number of CPU cores available to the process.
This allows creating alerting rules on CPU saturation with the following query:

    rate(process_cpu_seconds_total[5m]) / process_cpu_cores_available > 0.9

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2107
2022-01-31 20:25:15 +02:00
Aliaksandr Valialkin
377bb06b47 lib/cgroup: set GOGC to 50 by default if it isn't set
This should reduce memory usage for typical VictoriaMetrics workloads by up to 50%
2021-07-05 12:34:01 +03:00
Aliaksandr Valialkin
66c6976723 lib/cgroup: document the ability to detect cgroup v2 memory and cpu limits. This is follow-up for b50024812e 2021-05-13 09:27:35 +03:00
Nikolay
8743bf541f adds cgroupsv2 support (#1283)
* adds cgroupv2 limits support
https://github.com/VictoriaMetrics/VictoriaMetrics/issues/1269

* small fix

* changes Atoi to ParseUint
2021-05-13 09:27:33 +03:00
Aliaksandr Valialkin
2b36eb3d82 lib/cgroup: follow-up after b9bf3cbe3e 2021-02-08 16:01:26 +02:00
Nikolay
32603f57cc refactored cgroups limits, (#1061)
adds tests, remove os.Exec
2021-02-08 16:01:26 +02:00
Aliaksandr Valialkin
1a237c6903 all: properly handle CPU limits set on the host system/container
This can reduce memory usage on systems with enabled CPU limits.

Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/946
2020-12-08 21:07:03 +02:00
Aliaksandr Valialkin
5e998e597a lib/cgroup: do not adjust the number of detected CPU cores via /sys/devices/system/cpu/online
The adjustement increases the resulting GOMAXPROC by 1, which looks confusing to users
as outlined at https://github.com/VictoriaMetrics/VictoriaMetrics/issues/685#issuecomment-698595309
2020-09-29 13:55:53 +03:00
Aliaksandr Valialkin
89d652b583 lib/cgroup: attempt to obtain available CPU cores via /sys/devices/system/cpu/online
See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/685#issuecomment-674423728
2020-09-22 23:27:26 +03:00
Aliaksandr Valialkin
d2f6f96e4a lib/memory: fall back to reading hierarchical memory limit in cgroups when the default limit isn't set
Updates https://github.com/VictoriaMetrics/VictoriaMetrics/issues/699
2020-09-04 00:04:57 +03:00
Aliaksandr Valialkin
45e770ed20 lib/cgroup: limit the maximum GOMAXPROCS value to the number of available CPU cores
There is no sense in setting GOMAXPROCS to value higher than the number of available CPU cores.
2020-08-28 09:49:22 +03:00
Aliaksandr Valialkin
6721e47ae9 app: respect CPU limits set via cgroups
Update GOMAXPROCS to limits set via cgroups. This should reduce CPU trashing and reduce memory usage
for cases when VictoriaMetrics components run in containers with CPU limits.

See https://github.com/VictoriaMetrics/VictoriaMetrics/issues/685
2020-08-11 23:01:03 +03:00