Hi, md! On Sep 08, [email protected] wrote: > Does anybody have any thoughts on what would be involved with getting > Aria Tables to have an option to be memory only (Fully cached with no > disk writing, power off means data loss)
It should be quite easy, I suppose. One would just need to add some option that would prevent flushing pages of these tables from the page cache down to disk. > ARIA support row locking instead of Memory Tables which only have > Table locking. Table locking sucks for anything that is heavy > read/write. Aria does not support row locking. > Right now I am using RAM DISKs to store my memory based ARIA tables so > I can get decent speed for heavy read/write sections of the DB. > > But there is a bit of a operations headache where I have to allocate > the RAM disks on system boot and the storage strategy of Aria does not > release disk blocks when records are deleted, those spaces are left > for future records by setting the deleted flag back to undeleted. So > the memory pool is not used very effectively. > > So deleting records from a RAM disk ARIA table means that I have to > vaccuum the tables using ALTER table every so often or I could run out > of memory. (Very bad for ramdisks) > > If the ARIA cache routines could allocate memory dynamically from the > global heap and return the memory upon delete operations, that would > be a better options. And of course, no data is written to disk, just > kept in cache. Allocating memory dynamically would be more difficult that simply not flushing pages. But anyway, the point is moot, because Aria uses table-level locking. Regards, Sergei _______________________________________________ Mailing list: https://launchpad.net/~maria-developers Post to : [email protected] Unsubscribe : https://launchpad.net/~maria-developers More help : https://help.launchpad.net/ListHelp
