[Xapian-discuss] FLAG_WILDCARD, add_database and performance

[Oliver Flimm]

Hi,

On Mon, Aug 04, 2008 at 09:32:37AM +0100, Olly Betts wrote:
> On Mon, Aug 04, 2008 at 09:45:47AM +0200, Oliver Flimm wrote:
> > On Mon, Aug 04, 2008 at 08:57:30AM +0200, Oliver Flimm wrote:
> > > > Could you profile to find where the time is spent?  Some tips are here:
> > > > 
> > > > http://trac.xapian.org/wiki/ProfilingXapian
> > 
> > it looks like some routines in libc get called alot when using a
> > wildcard search.
> 
> Hmm, yes.  Can you install the package libc6-dbg and repeat?  That
> should then give us actual function names in libc.

Here are the results:

CPU: Core 2, speed 2666.68 MHz (estimated)
Counted CPU_CLK_UNHALTED events (Clock cycles when not halted) with a
unit mask of 0x00 (Unhalted core cycles) count 100000
samples  %        image name               app name
symbol name
-------------------------------------------------------------------------------
  18       100.000  libc-2.3.6.so            libc-2.3.6.so
__rpc_thread_destroy
1915840  80.4207  libc-2.3.6.so            libc-2.3.6.so
_int_malloc
  1915840  99.9993  libc-2.3.6.so            libc-2.3.6.so
_int_malloc [self]
  6        3.1e-04  libstdc++.so.6.0.8       libc-2.3.6.so
(no symbols)
  5        2.6e-04  libxapian.so.15.5.1      libc-2.3.6.so
(no symbols)
  1        5.2e-05  libc-2.3.6.so            libc-2.3.6.so
memcpy
  1        5.2e-05  libmysqlclient.so.15.0.0 libc-2.3.6.so
(no symbols)
-------------------------------------------------------------------------------

Regards,

Oliver

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