It has been almost a week and no-one has answered my question about
turning off caching in the latest xymon code
I checked the source code and my –no-cache flag seems to be correct, but
the caching is continuing and is causing holes ( no update for a five
minute period) in the rrd files. I also found where –no-cache is set
within do_rrd.c and hobbitd_rrd.c, so I am assuming that there is a bug
here that does not turn off caching using the –no-cache flag.
So for a temporary fix, can I just set:
do_rrd.c:int use_rrd_cache = 1; /* Use the cache by default */
to
do_rrd.c:int use_rrd_cache = 0; /* Don’t use the cache by default */
recompile and move the binary over or would I be wasting my time as the
caching would still continue?
Tom
------------------------------------------------------------------------
*From:* Stewart, Tom L. [mailto:Tom.Stewart (at) landsend.com]
*Sent:* Friday, November 13, 2009 3:19 PM
*To:* hobbit (at) hswn.dk
*Subject:* [hobbit] Question about using no-cache on rrd for xymon
4.3.0.0.beta-2
We are having issues with rrd leaving 5-10 minute intervals of no data
for items such as cpu load on various systems. Most of the time it
happens three times in a row like at 2, 3 and 4 pm. I am not finding
anything is the logs on either the client or server. Some googling
indicated that the issue may go away by using the no-cache option for
RRD. I have added it to the hobbitlaunch.cfg as such:
hobbitlaunch.cfg: CMD hobbitd_channel --channel=status
--log=$BBSERVERLOGS/rrd-status.log hobbitd_rrd --no-cache
--extra-tests=cpucisco,ifaload,ifload,vload,wphlstat,wperrors
--extra-script=/home/xymon/server/ext/extra-rrd.pl --rrddir=$BBVAR/rrd
hobbitlaunch.cfg: CMD hobbitd_channel --channel=data
--log=$BBSERVERLOGS/rrd-data.log hobbitd_rrd --no-cache
--extra-tests=mpstat,zonestat
--extra-script=/home/xymon/server/ext/rrd_data.pl --rrddir=$BBVAR/rrd
This is on a 32 bit red hat system and when I do a ps –ef | grep rrd I
show the following:
xymon 7635 7599 0 14:26 ? 00:00:01 hobbitd_channel
--channel=status --log=/home/xymon/logs/rrd-status.log hobbitd_rrd
--no-cache --extra-tests=cpucisco,ifaload,ifload,vload,wphlstat,wperrors
--extra-script=/home/xymon/server/ext/extra-rrd.pl
--rrddir=/home/xymon/data/rrd
xymon 7636 7599 0 14:26 ? 00:00:00 hobbitd_channel
--channel=data --log=/home/xymon/logs/rrd-data.log hobbitd_rrd
--no-cache --extra-tests=mpstat,zonestat
--extra-script=/home/xymon/server/ext/rrd_data.pl
--rrddir=/home/xymon/data/rrd
xymon 7672 7635 0 14:26 ? 00:00:07 hobbitd_rrd --no-cache
--extra-tests=cpucisco,ifaload,ifload,vload,wphlstat,wperrors
--extra-script=/home/xymon/server/ext/extra-rrd.pl
--rrddir=/home/xymon/data/rrd
xymon 7681 7636 0 14:26 ? 00:00:03 hobbitd_rrd --no-cache
--extra-tests=mpstat,zonestat
--extra-script=/home/xymon/server/ext/rrd_data.pl
--rrddir=/home/xymon/data/rrd
So it looks like it is in effect, but looking at the tmp file I still
see the following:
srw-rw-rw- 1 xymon xymon 0 Nov 13 14:26 rrdctl.7672
srw-rw-rw- 1 xymon xymon 0 Nov 13 14:26 rrdctl.7681
When I stop and restart xymon I still get messages such as:
rrd-status.log:2009-11-13 14:26:09 Cache flush completed
rrd-status.log:2009-11-13 14:26:18 Peer not up, flushing message queue
So my question is have I placed the –no-cache in the wrong sequence on
the startup command or is that been taken out of beta-2?
Thank you,
Tom