I had the same problems as you with missing/gappy data, however –nocache seemed to work just fine. I haven’t had any issues since I started using it. Are you sure you’re calling it correctly?
CMD hobbitd_channel --channel=data --log=/dev/null hobbitd_rrd --no-cache --rrddir=/var/lib/xymon/rrd
CMD hobbitd_channel --channel=status --log=/dev/null hobbitd_rrd --no-cache --rrddir=/var/lib/xymon/rrd
… are what my rrddata and rrdstatus sections are using, respectively
Regards,
-jc
From: Stewart, Tom L. [mailto:user-f210f371749e@xymon.invalid]
Sent: Thursday, November 19, 2009 7:48 AM
To: user-ae9b8668bcde@xymon.invalid
Subject: RE: [hobbit] Question about using no-cache on rrd for xymon 4.3.0.0.beta-2
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:user-f210f371749e@xymon.invalid]
Sent: Friday, November 13, 2009 3:19 PM
To: user-ae9b8668bcde@xymon.invalid
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