-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Brian Aker wrote: > Hi! > > I want to come up with a standard behavior for failure to allocate > memory. From this blog entry, > http://ronaldbradford.com/blog/are-you-monitoring-rss-vsz-2009-03-08/,I quote > > > "Monitoring MySQL Memory is a rather critical task because you can’t > limit MySQL’s usage of physical memory resources. Improperly configured > servers running MySQL can crash because you don’t understand memory usage." > > Right now memory allocation in Drizzle is the same as MySQL, namely the > behavior is mostly undefined (and allocation failures are not always > caught). Up till a certain version MySQL did capture these errors in > most cases, but in recent time these failures have just been ignored. > > This is my proposal: > > 1) Any memory failure on startup causes an immediate shutdown.
+1. This can be entirely done in a single try/catch block in the drizzled.cc:init_server_components() function. Since it's not time-critical or threaded code, using std::bad_alloc exception is perfectly fine here and would clean up a crap-ton of checks for ENOMEM. > 2) Memory failure within a session disconnects the session (and frees > all memory that the session allocated). +1. This can also be accomplished with localized exceptions, but more planning is needed. > 3) Failure of memory on connection from the user disallows the login. - -1 Agree with Monty here...perhaps we should have some fallback routine to free unneeded memory and attempt to proceed with the sessions' execution? > 4) Memory failure in any system other then a session usage causes the > server to shutdown (and attempts a graceful shutdown). +1 > What am I missing? Is the above a good policy for design? > > Cheers, > -Brian > > -- > _______________________________________________________ > Brian "Krow" Aker, brian at tangent.org > Seattle, Washington > http://krow.net/ <-- Me > http://tangent.org/ <-- Software > _______________________________________________________ > You can't grep a dead tree. > > > > > _______________________________________________ > Mailing list: https://launchpad.net/~drizzle-discuss > Post to : [email protected] > Unsubscribe : https://launchpad.net/~drizzle-discuss > More help : https://help.launchpad.net/ListHelp -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkm1RMwACgkQ2upbWsB4UtGmwgCgh4p2Q9YAlVEQk/nNYWIvOgQJ 3uYAmwXw6KfR6M5cMD0fMCLtFcPMzfwy =k0Cp -----END PGP SIGNATURE----- _______________________________________________ Mailing list: https://launchpad.net/~drizzle-discuss Post to : [email protected] Unsubscribe : https://launchpad.net/~drizzle-discuss More help : https://help.launchpad.net/ListHelp
