It turns out, on some kernels (notably - CentOS6) there is an empty line
inserted at the beginning of /sys/devices/system/node/node*/meminfo
files. The leads to node_exporter crash on such kernels.
Fix this by checking for empty string first.
Signed-off-by: Pavel Borzenkov <pavel.borzenkov@gmail.com>
Add new collector which exposes the content of /sys/kernel/mm/ksm
directory. This directory contains control and statistics files for
Kernel Samepage Merging daemon.
The collector is not enabled by default.
Signed-off-by: Pavel Borzenkov <pavel.borzenkov@gmail.com>
It is sometimes useful to understand the distribution of free/occupied
memory between NUMA nodes to deal with performance problems. To do so,
add new meminfo_numa collector that enables exporting of per node
statistics along with unit and end-to-end tests for it.
Signed-off-by: Pavel Borzenkov <pavel.borzenkov@gmail.com>