On Wed, 6 Sep 2006 18:26:46 -0400 Jonathan Vanasco <[EMAIL PROTECTED]> wrote:
> > On Sep 6, 2006, at 6:01 PM, Frank Wiles wrote: > > > It didn't disappear, and it isn't "shared" like the type of > > sharing we talk about with mod_perl/Apache. It's not CoW sharing. > I know. > > > The shared memory you're talking about here is held by the > > postmaster > > daemon and is used to store frequently requested data to be used > > by the forked children via SysV IPC. > > Yes. I know that. pg_stop is the stopping of the postmaster daemon > -- not clients ( apache stop will kill the pids of the clients ). > > > And yeah, PostgreSQL cleans up it's shared memory when it exits > > like it should. > > No, its not. thats the point of my post. Sorry I guess I misunderstood what you were saying. > On my system, shared memory that was allocated to postgres is not > being returned. postgres's exit releases the lock on memory-- ipcs > shows nothing allocated. but the kernel never gains any of that > shared mem. i only see about the size of the resident memory of the > postmaster instance and the clients returned. > > I'm inclined to think this 'leak' is in postgres and not in > Apache/MP/ DBI, because it happens to pg via the command line > > the long running process where i found this behavior started off at > about 850mb of free memory. earlier today my machine was down to > 241mb free- a stop/wait/start of apache brought me to 317 and a > restart of pg brought me to 321. thats about 500mb vanished. > > then i remembered this post, started poking around , and saw memory > disappear and never made available in proportion to the pg vsize > ( the clients themselves are nothing). Is that 500MB that "vanished" in used, buffers, or cached? Just because it isn't listed in "free" doesn't mean it isn't "free" from a "Available memory I can use" standpoint. For example, your system will reclaim memory from cached and buffers when it runs out of "free". --------------------------------- Frank Wiles <[EMAIL PROTECTED]> http://www.wiles.org ---------------------------------
