Previously the raw time difference was used which includes the network trip time
between the node and the ntp server. This makes setting alerts off the value
troublesome as it depends on the latency as well as the clock offset.
logind provides a nice interface to find out about the numbers of sessions
on a system; it is used on most Linux distributions, even those which
aren't using systemd.
The exporter exposes the total number of sessions indexed by the following
attributes:
* seat
* type ("tty", "x11", ...)
* class ("user", "greeter", ...)
* remote ("true"/"false")
This removes the requirement to run `node_exporter` as root or with read
access to `/dev/kmem` in order to get CPU usage statistics.
Once FreeBSD adds a macro for the `kern.cp_times` sysctl, the
`setupSysctlMIBs()` function should be replaced by usage of the macro.
When compiling `20ecedd0b4c983bd7b88f97cd7a21461988a6c12` with GNU make (`gmake`) on FreeBSD 10.2-RELEASE, I get the following error:
```
collector/filesystem_bsd.go:60: non-bool mnt[i].f_flags & MNT_RDONLY (type C.uint64_t) used as if condition
Makefile.COMMON:85: recipe for target 'node_exporter' failed
gmake: *** [node_exporter] Error 2
```
This problem is fixed by this patch.
When compiling `20ecedd0b4c983bd7b88f97cd7a21461988a6c12` with GNU make (`gmake`) on FreeBSD 10.2-RELEASE, I get the following error:
```
collector/filesystem_bsd.go:60: non-bool mnt[i].f_flags & MNT_RDONLY (type C.uint64_t) used as if condition
Makefile.COMMON:85: recipe for target 'node_exporter' failed
gmake: *** [node_exporter] Error 2
```
This problem is fixed by this patch.
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>
The option to write out a memory profile to file was removed in a730cff.
Declaring flags as local variable does not only result in cleaner, more
testable code, but also ensures that the program won't compile anymore
when unused flags are left in place.
