prometheus/cadvisor
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Netlink: aggressively close cgroup fds

Browse Source 
Not closing the FDs manually means we have to rely on garbage collection
to run before cgroup FDs are closed. If the system is running a lot of
load probes at a high-frequency (i.e. dynamic housekeeping isn't backing
off because of load variations), we can end up hitting our FD limit due
to keeping around lots of (useless) FDs.
This commit is contained in:
Thomas Orozco 2016-04-05 14:23:57 +02:00
parent a6fdb9b445
commit ee8701aa97
2 changed files with 6 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
utils/cpuload/netlink/netlink.go
View File

@ -18,6 +18,7 @@ import (
"bytes"
"encoding/binary"
"fmt"
"os"
"syscall"
info "github.com/google/cadvisor/info/v1"
@ -219,10 +220,10 @@ func verifyHeader(msg syscall.NetlinkMessage) error {
// Get load stats for a task group.
// id: family id for taskstats.
// fd: fd to path to the cgroup directory under cpu hierarchy.
// cfd: open file to path to the cgroup directory under cpu hierarchy.
// conn: open netlink connection used to communicate with kernel.
func getLoadStats(id uint16, fd uintptr, conn *Connection) (info.LoadStats, error) {
msg := prepareCmdMessage(id, fd)
func getLoadStats(id uint16, cfd *os.File, conn *Connection) (info.LoadStats, error) {
msg := prepareCmdMessage(id, cfd.Fd())
err := conn.WriteMessage(msg.toRawMsg())
if err != nil {
return info.LoadStats{}, err

3
utils/cpuload/netlink/reader.go
View File

@ -66,11 +66,12 @@ func (self *NetlinkReader) GetCpuLoad(name string, path string) (info.LoadStats,
}
cfd, err := os.Open(path)
defer cfd.Close()
if err != nil {
return info.LoadStats{}, fmt.Errorf("failed to open cgroup path %s: %q", path, err)
}
stats, err := getLoadStats(self.familyId, cfd.Fd(), self.conn)
stats, err := getLoadStats(self.familyId, cfd, self.conn)
if err != nil {
return info.LoadStats{}, err
}