> Tatsuo, > > > Yes. However it would be pretty easy to modify pgpool so that it could > > cope with Slony-I. I.e. > > > > 1) pgpool does the load balance and sends query to Slony-I's slave and > > master if the query is SELECT. > > > > 2) pgpool sends query only to the master if the query is other than > > SELECT. > > > > Remaining problem is that Slony-I is not a sync replication > > solution. Thus you need to prepare that the load balanced query > > results might differ among servers. > > Yes, please, some of us are already doing the above ad-hoc. > > The simple workaround to replication lag is to calculate the longest likely > lag (<3 seconds if Slony is tuned right) and have the dispatcher (pgpool) > send all requests from that connection to the master for that period. Then > it switches back to "pool" mode where the slaves may be used.
Can I ask a question? Suppose table A gets updated on the master at time 00:00. Until 00:03 pgpool needs to send all queries regarding A to the master only. My question is, how can pgpool know a query is related to A? -- Tatsuo Ishii > Of course, all of the above is only useful if you're doing a web app where > 96% > of query activity is selects. For additional scalability, put all of your > session maintenance in memcached, so that you're not doing database writes > every time a page loads. > > -- > Josh Berkus > Aglio Database Solutions > San Francisco > ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly