Comment # 3
on bug 1110
from Frank Ch. Eigler
A quick update on pcp 3.11.5:
% for i in `seq 0 5`; do docker run --rm busybox sleep 999 &; done
% docker ps # pick any one
% pmval --container=ONE_OF_THEM pmcd.hostname
while in another window
# strace -p `pgrep pmdaroot`
Each and every fetch of just one container's pmcd.hostname metric involves this
much work from pmdaroot ... and that's for a small fixed set of containers.
) = 1 (in [6])
recvfrom(6, "\1\220\0\0$\0\0\0\0\0\0\0\2\0\0\0\0\0\0\0\f\0\0\0tiny_lea"...,
8192, 0, NULL, NULL) = 36
stat("/var/lib/docker/containers", {st_mode=S_IFDIR|0700, st_size=4096, ...}) =
0
stat("/var/lib/lxc", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
open("/var/lib/docker/containers/e0316c46a124f00a6af91f5345dbfe2ae302f221c8914d4c62d6ce1d326d4e6f/config.v2.json",
O_RDONLY) = 11
close(11) = 0
stat("/var/lib/docker/containers/e0316c46a124f00a6af91f5345dbfe2ae302f221c8914d4c62d6ce1d326d4e6f/config.v2.json",
{st_mode=S_IFREG|0666, st_size=2377, ...}) = 0
open("/var/lib/docker/containers/830962e85e49c5574f837c5f48c91559d7c20407eef04c45780ae6a387ad9149/config.v2.json",
O_RDONLY) = 11
close(11) = 0
stat("/var/lib/docker/containers/830962e85e49c5574f837c5f48c91559d7c20407eef04c45780ae6a387ad9149/config.v2.json",
{st_mode=S_IFREG|0666, st_size=2382, ...}) = 0
open("/var/lib/docker/containers/fc06343e7ec4077174d002e31889ae48f3fef7ee617a9c0b8fa93b3fba0d405c/config.v2.json",
O_RDONLY) = 11
close(11) = 0
stat("/var/lib/docker/containers/fc06343e7ec4077174d002e31889ae48f3fef7ee617a9c0b8fa93b3fba0d405c/config.v2.json",
{st_mode=S_IFREG|0666, st_size=2381, ...}) = 0
open("/var/lib/docker/containers/6ff13ca4a1936a71131f4ec04041d072d2acaa681276cd07ecbe19bbcd1e1610/config.v2.json",
O_RDONLY) = 11
close(11) = 0
stat("/var/lib/docker/containers/6ff13ca4a1936a71131f4ec04041d072d2acaa681276cd07ecbe19bbcd1e1610/config.v2.json",
{st_mode=S_IFREG|0666, st_size=2378, ...}) = 0
open("/var/lib/docker/containers/d5b272e2a5b4515de989b7deee851947cb6740beb987336e61385b770623395d/config.v2.json",
O_RDONLY) = 11
close(11) = 0
stat("/var/lib/docker/containers/d5b272e2a5b4515de989b7deee851947cb6740beb987336e61385b770623395d/config.v2.json",
{st_mode=S_IFREG|0666, st_size=2378, ...}) = 0
open("/var/lib/docker/containers/6b55c8b9e9173d603d464195fd824278e660821a7f6d731e2196d89c53fd6628/config.v2.json",
O_RDONLY) = 11
close(11) = 0
stat("/var/lib/docker/containers/6b55c8b9e9173d603d464195fd824278e660821a7f6d731e2196d89c53fd6628/config.v2.json",
{st_mode=S_IFREG|0666, st_size=2377, ...}) = 0
open("/proc/10919/ns/uts", O_RDONLY) = 11
setns(11, CLONE_NEWUTS) = 0
close(11) = 0
uname({sysname="Linux", nodename="6b55c8b9e917", ...}) = 0
setns(10, CLONE_NEWUTS) = 0
sendto(6, "\2\220\0\0$\0\0\0\0\0\0\0\2\0\0\0\247*\0\0\f\0\0\0006b55c8b9"...,
36, MSG_NOSIGNAL, NULL, 0) = 36
select(15, [0 3 6 7 8 9], NULL, NULL, NULL