On 2008-07-15 11:30, Damien Deville wrote: > Dear Clamav-Devel, > > Here is a set of patches of libclamav and clamd for clamav-0.93.3 that > reduces the loading time of compressed antiviral database in cvd files. > They can be found at the following url: http://pbmtp.free.fr/clamav/ > > We noticed by instrumenting the loading of database that the > uncompressing of compressed cvd files is performed line by line using > gzgets function and that this function is the hotspot of the loading time. > > The proposed patch optimizes the loading of compressed database (in cvd) > by uncompressing big blocks of compressed data using gzread, store them > into a cache and read lines of uncompressed data from the cache. > The patch add two new functions to initialize a cache of given size and > one to free the allocated memory for the cache. > cli_dbgets use a new function called cli_dbgets_cache when a cache > pointer is found. > > To use the cache simply call cl_dbcache_init(size_in_kb) before calling > cl_load() and after load release the allocated memory using > cl_dbcache_cleanup(). Such a patch is provided for clamd. > > Here are some benchmark results concerning the loading time on a VIA C3 > Samuel 2 at 400.91-MHz > > Loading of compressed cvd (no cache): 4:13.54 > Loading of compressed cvd (cache of 16KB): 1:11.75 > Loading of uncompressed cvd: 0:53.68 >
Excellent! > You can see that loading time is closed to be divided by a factor of 4. > > We would be happy if some of you could have a look at the patchs and > test them and report any issues or remarks. > Please open an enhancement bugreport on bugs.clamav.net, so that we can assign a target milestone for this. Best regards, --Edwin _______________________________________________ http://lurker.clamav.net/list/clamav-devel.html Please submit your patches to our Bugzilla: http://bugs.clamav.net
