Without APC, there should be even more of an improvement with the Thrift PHP extension.
----- "Rauan Maemirov" <ra...@maemirov.com> wrote: > What about APC? Did you turn it on? > > 2010/3/30 Julian Simon <jsi...@jules.com.au>: > > Hi, > > > > I've been trying to benchmark Cassandra for our use case and have > been > > seeing poor performance on both writes and (extremely) poor > > performance on reads. > > > > Using Cassandra 0.51 stable & thrift-0.2.0. > > > > It turns out all the CPU time is going to the PHP client process - > the > > JVM operating the Cassandra server isn't breaking much of a sweat. > > > > For reads the latency is often up to 1 second to fetch a row > > containing ~2000 columns, or around 300ms to fetch a 500-column > wide > > row. This is with get_slice(), and a predicate specifying the start > & > > finish range. > > > > Using cachegrind and inspecting the code inside the Thrift bindings > > makes it pretty clear why the performance is so bad, particularly > on > > reads. The biggest culprit is the translation code which casts data > > back and forth into binary representations for sending over the > wire > > to the Cassandra server. > > > > There seems to be some 32-bit specific code which iterates heavily > > apparently due to a limitation in PHPs implementation of LONGs. > > > > However, testing on a 64-bit host doesn't yield any performance > improvement. > > > > More surprisingly, if I compile and enable the PHP native thrift > > bindings (following this guide > > https://wiki.fourkitchens.com/display/PF/Using+Cassandra+with+PHP) > > read performance actually degrades by another 50%. I have verified > > that the Thrift code is recognizing and using the native PHP > functions > > provided by the library. > > > > I've tested all of this on both 32-bit and 64-bit installations of > > both PHP 5.1 & 5.2. Results are the same in all cases. > > > > My environment is on vanilla CentOS 5.4 server installations inside > > VMWare on a 4 core 64bit host with plenty of RAM and fast disks. > > > > Has anyone been able to produce decent performance with PHP & > > Cassandra? If so, how have you done it? > > > > Thanks, > > Jules > > -- David Strauss | da...@fourkitchens.com | +1 512 577 5827 [mobile] Four Kitchens | http://fourkitchens.com | +1 512 454 6659 [office] | +1 512 870 8453 [direct]
