For the last three days, I am having serious performance problems with
my RT installation.
The first thing that I noticed had something to do with table locking.
I have a script that makes a backup (mysqldump --opt --force) of my
RT database every night. It is what gave me the 1st sign of a problem
when it reported the following error:
/usr/local/bin/mysqldump: Got error: 1015: Can’t lock file
(errno: 149) when using LOCK TABLES
Looking at my
top output, this is what mysqld is doing on my server:
PID USERNAME PRI NICE SIZE RES STATE C TIME WCPU CPU COMMAND
86774 mysql 20 0 673M 542M kserel 0 19.8H 103.37% 103.37% mysqld
Now I decided to use
mytop as well just to see what queries are being
run on the database and here is the output:
MySQL on localhost (4.0.23a)
Queries: 778.1k qps: 18 Slow: 29.3k Se/In/Up/De(%): 73/18/06/00
qps now: 10 Slow qps: 0.0 Threads: 7 ( 4/ 6) 63/24/08/00
Cache Hits: 105.0k Hits/s: 2.4 Hits now: 0.2 Ratio: 18.4% Ratio now: 3.1%
Key Efficiency: 97.9% Bps in/out: 1.5k/13.1k Now in/out: 780.6/ 2.6k
Id User Host/IP DB Time Cmd Query or State -- ---- ------- -- ---- --- ----------
23497 root localhost test 0 Query show full processlist
23307 rt3 mail rt3 2 Query SELECT main.* FROM CachedGroupMembers main WHERE ((main.MemberId = 13592
22989 rt3 mail rt3 4 Query SELECT main.* FROM CachedGroupMembers main WHERE ((main.MemberId = 13591
23274 rt3 mail rt3 4 Query SELECT main.* FROM CachedGroupMembers main WHERE ((main.MemberId = 13592
So many of queries like that one are showing.
My DB is on a remote box different than the host that runs the web UI.
I am suspecting something database related and was wondering if
someone has an idea/clue on what I should be checking on as a
first step towards the diagnostics.
cheers - wash
Odhiambo Washington . WANANCHI ONLINE LTD (Nairobi, KE) |
wash at wananchi _ dot _ com . 1ere Etage, Loita Hse, Loita St., |
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