http://highscalability.com/blog/2011/6/21/running-tpc-c-on-mysqlrds.html
Results Analysis The benchmark results are surprising. With hardly any dependency on the database size, MySQL reaches its optimal throughput at around 64 concurrent users. Anything above that causes throughput degradation. Throughput is improving as machines get stronger. However, there is a sweet-spot, a point where adding hardware doesn’t help performance. The sweet spot is around the XL machine, which reaches a throughput of around 7000 tpm. 2XL and 4XL machines don’t improve this limit. It would seem that the Scale-Up scalability approach is rather limited, and bounded. And unfortunately, has some rather close bounds. So, what’s the bottleneck? - CPU is unlikely candidate, as CPU power doubles on 2XL and quadruple on 4XL machines. - I/O is also an unlikely candidate. Since machines memory (RAM) doubles on 2XL and quadruple on 4XL machines. More RAM means more database cache buffers, thus reduced I/O. - Concurrency? Number of concurrent users? Well we saw that optimal throughput is achieved with around 64 concurrent sessions on the database. See figure 4b in the benchmark report. While with 1 user the throughput 1,000 transactions per user, with 256 users it drops to 1 transaction per user! Would be interesting to check how does Firebird behaves. Roman ------------------------------------------------------------------------------ Simplify data backup and recovery for your virtual environment with vRanger. Installation's a snap, and flexible recovery options mean your data is safe, secure and there when you need it. Data protection magic? Nope - It's vRanger. Get your free trial download today. http://p.sf.net/sfu/quest-sfdev2dev Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
