[Dazuko-devel] Dazuko driver takes lots of cpu time, bottleneck discovered

[Tikka, Sami]

When I have dazuko driver loaded and our on-access-scanner running, I
frequently see my system go into a state where the system takes 50-90% of all
cpu time (reported by 'top'). 

This usually happens after accessing a lot of files, like hundreds of
thousands. (Compile XFree86 and glibc)

When I kill the on-access-scanner process, the system cpu usage goes down to
almost nothing, i.e. the normal situation.

During such a system-load situation I ran oprofile and this is what it
reports:

samples  %        app name                 symbol name
1606     56.0950  dazuko.o                 xp_compare_file
523      18.2676  dazuko.o                 dazuko_mark_hash_dirty
93        3.2483  dazuko.o                 dazuko_get_hash
[deleted the rest]

It seems to me that there is a linked list data structure in dazuko that is
becoming a bottleneck.

At the moment I do not have a patch to fix this, I thought I'd just report
what I have seen. 

Anyone else seen this? Is anyone working on a fix?

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