On Thu, Feb 06, 2003 at 12:30:03AM -0500, Tom Lane wrote: > I have a feeling that what the questioner really means is "how can I > limit the resources consumed by any one database user?" In which case
(I'm moving this to -hackers 'cause I think it likely belongs there.) I note that this question has come up before, and several people have been sceptical of its utility. In particular, in this thread <http://groups.google.ca/groups?hl=en&lr=&ie=UTF-8&threadm=Pine.LNX.4.21.0212221510560.15719-100000%40linuxworld.com.au&rnum=1&prev=/groups%3Fq%3Dlimit%2Bresources%2B%2Bgroup:comp.databases.postgresql.*%26hl%3Den%26lr%3D%26ie%3DUTF-8%26selm%3DPine.LNX.4.21.0212221510560.15719-100000%2540linuxworld.com.au%26rnum%3D1> (sorry about the long line: I just get errors searching at the official archives) Tom Lane notes that you could just run another back end to make things more secure. That much is true; but I'm wondering whether it might be worth it to limit how much a _database_ can use. For instance, suppose I have a number of databases which are likely to see sporadic heavy loads. There are limitations on how slow the response can be. So I have to do some work to guarantee that, for instance, certain tables from each database don't get flushed from the buffers. I can do this now by setting up separate postmasters. That way, each gets its own shared memory segment. Those "certain tables" will be ones that are frequently accessed, and so they'll always remain in the buffer, even if the other database is busy (because the two databases don't share a buffer). (I'm imagining the case -- not totally imaginary -- where one of the databases tends to be accessed heavily during one part of a 24 hour day, and another database gets hit more on another part of the same day.) The problem with this scenario is that it makes administration somewhat awkward as soon as you have to do this 5 or 6 times. I was thinking that it might be nice to be able to limit how much of the total resources a given database can consume. If one database were really busy, that would not mean that other databases would automatically be more sluggish, because they would still have some guaranteed minimum percentage of the total resources. So, anyone care to speculate? -- ---- Andrew Sullivan 204-4141 Yonge Street Liberty RMS Toronto, Ontario Canada <[EMAIL PROTECTED]> M2P 2A8 +1 416 646 3304 x110 ---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives? http://archives.postgresql.org
