Thanks Gabriel It's good to hear it. You can co-ordinate with me in relation to both areas. A small number of other developers are also involved in the developments in those areas, although not specifically what you are interested in.
I should be able to suggest a couple of tests to start with to find out about the speed and other implications of different options. Regards Fred ----- Original Message ----- From: "Gabriel Lawrence" <[EMAIL PROTECTED]> To: "fredt" <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: 13 June 2002 22:20 Subject: Re: [Hsqldb-developers] Performance Questions... I'd love to get involved in developing the software further and contributing my work. As far as the shutdown compact stuff goes, that may or may not be helpful in my specific case. What we have is basically a log of activity so its really a database that grows over time. because of this there shouldn't be that much that is solely air in the sense that its dead rows and so forth. Instead, the issue is that some of these rows have a bunch of text in em. Anyway, I'm thinking that gzip would make a big difference. When I was storing this data in a random access file, putting the stuff in as gziped binary made a big difference over putting the stuff in as some kind of xml serialized object. Clearly what you guys are doing with your database formit lies somewhere in between. Anyway, I'd be interested in implementing a compressed cached table scheme... Let me know if there is anyone specifically I should coordinate with. I'll check out the patch and feature trackers for info on how to tune queries... I suppose nobody has done a set showplan option similar to what oracle/sybase have? that might be a handy little addition no? Something else I'd be willing to look at doing. -gabe On Thu, 2002-06-13 at 11:00, fredt wrote: > Hi Gabriel, > > Some of these issues have been discussed in the sourceforge site. The patch > tracker and feature request tracker have at least a couple of items related > to the second point. Re the first point, the main thing to do is issue the > SHUTDOWN COMPACT command periodically. Using a compressed storage format is > an also something we can do in the near future. > > If you want to get involved in developing the software further and > contributing your work, please say so and we'll help you get started. > > Fred Toussi > > ----- Original Message ----- > From: "Gabriel Lawrence" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: 12 June 2002 21:55 > Subject: [Hsqldb-developers] Performance Questions... > > > Howdy, > > I'm using the 1.7.0 release embedded in our application. Its working > really well thanx! I have two issues with it right now, first the files > on teh filesystem seem to get pretty large relatively quickly. Looking > at them in an editor they appear to be the kind of thing that would > compress really nicely. I took a quick look at the persistence code and > it looks like it would be pretty easy to compress the rows before they > get written to disk and to uncompress them when they get read. Has > anyone else looked at this? what would be the perf implications? > > Second, I'm running a couple of queries that seemt to take a really long > time. I'm wondering if there is any way to get some insight into how the > engine is deciding to process the request? I'd like to see if it is > using my indexes or if there are other indexes I need to create? Can > anyone point me to the logic in the code that decides how to process a > request, I'd like to find out what the best way to create indexes is? If > I have several items in a where clause should I create compound indexes? > If this stuff is answered already somewhere sorry, please point me to > the location. > > Thanx, > =-gabe > > > _______________________________________________________________ > > Sponsored by: > ThinkGeek at http://www.ThinkGeek.com/ > _______________________________________________ > hsqldb-developers mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/hsqldb-developers > _______________________________________________________________ Don't miss the 2002 Sprint PCS Application Developer's Conference August 25-28 in Las Vegas - http://devcon.sprintpcs.com/adp/index.cfm?source=osdntextlink _______________________________________________ hsqldb-developers mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/hsqldb-developers
