> Ron Mayer expressed the thought that we're complicating needlessly the > UI for vacuum_delay, naptime, etc. He proposes that instead of having > cost_delay etc, we have a mbytes_per_second parameter of some sort. > This strikes me a good idea, but I think we could make that after this > proposal is implemented. So this "take 2" could be implemented, and > then we could switch the cost_delay stuff to using a MB/s kind of > measurement somehow (he says waving his hands wildly).
vacuum should be a process with the least amount of voodoo. If we can just have vacuum_delay and vacuum_threshold, where threshold allows an arbitrary setting of how much bandwidth we will allot to the process, then that is a beyond wonderful thing. It is easy to determine how much IO you have, and what you can spare. Joshua D. Drake > > Greg Stark and Matthew O'Connor say that we're misdirected in having > more than one worker per tablespace. I say we're not :-) If we > consider Ron Mayer's idea of measuring MB/s, but we do it per > tablespace, then we would inflict the correct amount of vacuum pain to > each tablespace, sleeping as appropriate. I think this would require > workers of different databases to communicate what tablespaces they are > using, so that all of them can utilize the correct amount of bandwidth. > > > I'd like to know if this responds to the mentioned people's objections. > -- === The PostgreSQL Company: Command Prompt, Inc. === Sales/Support: +1.503.667.4564 || 24x7/Emergency: +1.800.492.2240 Providing the most comprehensive PostgreSQL solutions since 1997 http://www.commandprompt.com/ Donate to the PostgreSQL Project: http://www.postgresql.org/about/donate PostgreSQL Replication: http://www.commandprompt.com/products/ ---------------------------(end of broadcast)--------------------------- TIP 9: In versions below 8.0, the planner will ignore your desire to choose an index scan if your joining column's datatypes do not match