[Koha] MySQL socket errors

[Robert Meltz]

Good Morning,

I am having problems with Koha returning the following error:

Koha error
The following fatal error has occurred:

Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2) at /usr/share/perl/5.8/CGI/Carp.pm line 314.
Compilation failed in require at /usr/share/koha/lib/C4/Auth.pm line 30.
BEGIN failed--compilation aborted at /usr/share/koha/lib/C4/Auth.pm line 30.
Compilation failed in require at /usr/share/koha/opac/cgi-bin/opac/opac-detail.pl line 25.
BEGIN failed--compilation aborted at /usr/share/koha/opac/cgi-bin/opac/opac-detail.pl line 25.


If I refresh the page it usually works, but this error appears more often than not since yesterday morning. I looked at some performance items suspecting that it may be related to slow response from the underlying system.

top - 08:31:07 up 20:01,  1 user,  load average: 0.21, 0.24, 0.25

# for i in a b; do hdparm -tT /dev/sd"$i"; done

/dev/sda:
 Timing cached reads:   2166 MB in  1.88 seconds = 1152.66 MB/sec
 Timing buffered disk reads:   22 MB in  3.28 seconds =   6.71 MB/sec

/dev/sdb:
 Timing cached reads:   2530 MB in  1.87 seconds = 1355.50 MB/sec
 Timing buffered disk reads:   34 MB in  3.32 seconds =  10.24 MB/sec

# mount
/dev/sda1 on / type ext3 (rw,relatime,errors=remount-ro)
proc on /proc type proc (rw,noexec,nosuid,nodev)
/sys on /sys type sysfs (rw,noexec,nosuid,nodev)
varrun on /var/run type tmpfs (rw,noexec,nosuid,nodev,mode=0755)
varlock on /var/lock type tmpfs (rw,noexec,nosuid,nodev,mode=1777)
udev on /dev type tmpfs (rw,mode=0755)
devshm on /dev/shm type tmpfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/sdb1 on /var/lib type ext3 (rw,relatime,errors=remount-ro)

It looks to me like the drives are slow. Not all that surprising considering that there are 6 virtual machines running off the same hyper-V host. What can I do to increase the performance under these conditions, or am I on the wrong track entirely? 

Best regards,
Robert Meltz