I'm not intimately familiar with how the scan cache works. I believe the cache size isn't limited at all. Adding a scan result to the cache should never fail, unless the system runs out of memory. I also would expect your first clamDscan scan to be slower than all subsequent scans of the same files up until a clamd database reload clears the cache.
A database check without a reload shouldn't clear the cache. If it does, that would certainly be a bug. I wish I had more time to dig in and investigate to help further but I'm a little overwhelmed with other tasks at present. I'll try to keep an eye on the thread to see if something comes up that I can be of help with. -Micah -----Original Message----- From: clamav-users <clamav-users-boun...@lists.clamav.net> On Behalf Of Dave Sill via clamav-users Sent: Thursday, October 1, 2020 11:02 AM To: G.W. Haywood via clamav-users <clamav-users@lists.clamav.net> Cc: Dave Sill <sil...@ornl.gov> Subject: Re: [clamav-users] clamd cache (was Re: clamscan --disable-cache) "G.W. Haywood via clamav-users" <clamav-users@lists.clamav.net> wrote: > Hi there, > > On Thu, 1 Oct 2020, Dave Sill via clamav-users wrote: > > >It looks like my point was lost in the noise ... > > Sorry, I guess it was late and I was in a hurry to get to bed. :( No worries. Thanks for your help. > >... on a much smaller scan, the cache made a huge difference. That > >tells me that the cache isn't large enough to significantly speed up > >large scans. > > It might be too soon to draw that conclusion. It's possible that the > daemon reloaded its database during your test, and I'd expect that to > cause any cached results to be discarded for obvious reasons. Fair enough. I re-ran the same scan three times after rebooting and got the following run times: 20:46 19:37 19:18 And the clamd logs show "SelfCheck: Database status OK" every 10 minutes but no DB updates. > >I don't see that the cache size is run-time configurable. Is that right? > > Correct, but I'd thought its size would be limited only by the RAM you > have free. If you look at the code in libclamav/cache.c you can see > that struct cache_set is just a few pointers, and if you only have 69k > files under your home directory I wouldn't expect storage of that many > sets of pointers to be an issue. > > I'll dig into this a bit more when I have chance if somebody doesn't > beat me to it. I only have 16 GB RAM on this system but it still shows 1 GB free. Maybe it limits itself somehow. -Dave _______________________________________________ clamav-users mailing list clamav-users@lists.clamav.net https://lists.clamav.net/mailman/listinfo/clamav-users Help us build a comprehensive ClamAV guide: https://github.com/vrtadmin/clamav-faq http://www.clamav.net/contact.html#ml _______________________________________________ clamav-users mailing list clamav-users@lists.clamav.net https://lists.clamav.net/mailman/listinfo/clamav-users Help us build a comprehensive ClamAV guide: https://github.com/vrtadmin/clamav-faq http://www.clamav.net/contact.html#ml
