Ühel kenal päeval, E, 2006-08-21 kell 21:46, kirjutas Fujii Masao: > Stefan Kaltenbrunner wrote: > > It is however async replication so you can loose data commited on the > > master but not yet replicated to the slaves in case you loose the master > > completely. > > Yes, here is an insufficient point of Slony-I, i think. > Most systems will not permit the committed data to be lost, so use is limited.
But any sync _replication_ system will have severe impact on performance. My guess is that for a full sync replication, going from 1 server to 2 will actually lower performance andsome small gains would be possible only starting from 3rd server. This has nothing to do with postgreSQL, but is just due to latencies of memory, disk and network and the need to do remote locking. My quess is based on using standard 100Gb ethernet. It may be possible to do better on some more advanced interconnects like myrinet. -- ---------------- Hannu Krosing Database Architect Skype Technologies OÜ Akadeemia tee 21 F, Tallinn, 12618, Estonia Skype me: callto:hkrosing Get Skype for free: http://www.skype.com ---------------------------(end of broadcast)--------------------------- TIP 2: Don't 'kill -9' the postmaster