On 10/10/2013 10:34 PM, F.Reenders@utwente.nl wrote:
Hi,
I tried the ramdisk. 48 Gb. I only have 64 Gb ram. It slowed down my system compared to the rrd's on disk. Maybe not enough memory left for all the other procs.
Then I added some more switches and my ramdisk wasn't big enough anymore. Now I have 280 switches/routers and 25000 ports a system load of 100+ and it's not making 1 cycle in 5 minutes. I tried 80,100 and 120 threads but when I get past the 80 threads the time to check one switch increases to much. Some routers take up to 200 seconds to check. I could setup a second system to check the routers...
A distributed option is a solution I think as I still need to add more switches.
I found that setting vm.dirty_writeback_centisecs in /etc/sysctl.conf to a value higher than the poll interval gave a lot of the benefits of the RAM disk without the overhead of managing it. I figure the risk of losing power or the system crashing is fairly low and the worst that can happen is the loss of a poll or two.
Paul