Hi Nick, My interpretation of those stats is that you are now out of memory as I always look at the Swap Used. You aren't using any. My experience with Linux is that the OS will take as much memory as it can/needs so it can look like you are maxed out on RAM usage or something, but you really need to pay attention to the swap used.
What I would be interested in seeing is that when you run your gbak backup go ahead and also run top. Are you seeing a lot of CPU time being spent in IOWait? If so that would mean that the CPU is being starved of data and is waiting around -- usually because the disk isn't fast enough. We normally only see this on virtual hosts though. -steve -- Steve Wiser President Specialized Business Software 6325 Cochran Road, Unit 1 Solon, OH 44139 www.specializedbusinesssoftware.com www.docunym.com (440) 542-9145 - fax (440) 542-9143 Toll Free: (866) 328-4936 On Fri, May 8, 2015 at 6:32 AM, Nick Upson [email protected] [firebird-support] <[email protected]> wrote: > > > Your mention of memory & paging got me thinking. I expected the output > below to show the memory was fully used such that more RAM would help > but unless I'm reading this wrong only 5.3Gb is being used and 2.4 GB is > unused so more RAM will be no help, can anyone confirm or put me right > > $ cat /proc/meminfo > MemTotal: 8309036 kB > MemFree: 307408 kB > Buffers: 59296 kB > Cached: 7433812 kB > SwapCached: 32 kB > Active: 5365212 kB > Inactive: 2470416 kB > HighTotal: 7471040 kB > HighFree: 18724 kB > LowTotal: 837996 kB > LowFree: 288684 kB > SwapTotal: 4095992 kB > SwapFree: 4095788 kB > Dirty: 186968 kB > Writeback: 0 kB > AnonPages: 342384 kB > Mapped: 140812 kB > Slab: 148064 kB > PageTables: 6824 kB > NFS_Unstable: 0 kB > Bounce: 0 kB > CommitLimit: 8250508 kB > Committed_AS: 2795520 kB > VmallocTotal: 116728 kB > VmallocUsed: 5788 kB > VmallocChunk: 110588 kB > HugePages_Total: 0 > HugePages_Free: 0 > HugePages_Rsvd: 0 > Hugepagesize: 2048 kB > > > Nick Upson, Telensa Ltd, Senior Operations Network Engineer > direct +44 (0) 1799 533252, support hotline +44 (0) 1799 399200 > > On 5 May 2015 at 15:21, Ann Harrison [email protected] > [firebird-support] <[email protected]> wrote: > >> >> >> Hi Nick, >> >> >> I have a system that is slowing down the longer it stays running and I'd >> like to know why. >> >> ... >> >> >> Is there any evidence I can gather before I reboot the system which I >> expect (from past experience) will return the system to the better >> performance >> >> >> Hmmm.... If rebooting will solve the problem and you don't have a very >> long running transaction, then I doubt that garbage accumulation or >> collection is the source of the problem. >> Nor is there anything else wrong with your physical database - >> fragmentation or whatever. >> I'd look at memory usage - using both Firebird and OS tools. Look for >> paging before you reboot. >> After you reboot, track memory usage daily or more often. It doesn't >> take much of a leak - or unfortunate caching - to built up over month of 27 >> tps. >> >> Accelerating the move to 2.5.4 would also be a good idea, both because it >> may correct the problem and because it probably offers better diagnostic >> tools for this sort of problem. >> >> Good luck, >> >> Ann >> >> > >
