On Thursday 08 November 2007 09:59:30 Steve Grubb wrote: > On Thursday 08 November 2007 09:56:51 Alexander Viro wrote: > > Easy enough to test - boot with audit disabled, run benchmarks, enable > > it, flush all caches (e.g. by memory pressure), rerun the benchmarks, > > compare... I don't think it will be serious problem, but if it will > > we can always look for trickier solutions. > > OK. I'll try to build a kernel and check this out. Might have some results > later.
OK, had a chance to do testing. First, the patch works. It solves the problem that was reported. Here's some performance numbers using the performance test I have at http://people.redhat.com/sgrubb/files/lspp-perf.tar.gz without patch boot with audit=0 audit disabled: 38.9 audit enabled: 42.3 without patch boot with audit=1 audit disabled: 41.4 audit enabled: 42.9 with patch boot with audit=0 audit disabled: 38.6 audit enabled: 43.8 with patch boot with audit=1 audit disabled: 44.2 audit enabled: 44.6 So, when audit is enabled at boot. There is virtually no performance difference between enabled and not. The old way, we had a 4% performance improvement when audit was disabled. Looking at the audit=0 case, there is about a 3.5% performance hit when audit is enabled with the new patch. The old way, audit disabled was always significantly faster ~ %4. With the patch its only about 1% faster. -Steve -- Linux-audit mailing list [email protected] https://www.redhat.com/mailman/listinfo/linux-audit
