Sander Striker wrote:
From: Ryan Bloom [mailto:[EMAIL PROTECTED] Sent: 06 February 2002 18:02
-----Original Message----- From: Justin Erenkrantz [mailto:[EMAIL PROTECTED] Sent: Wednesday, February 06, 2002 8:59 AM To: Sander Striker Cc: [email protected] Subject: Re: [PATCH] Free memory over a certain threshold back to the system
On Wed, Feb 06, 2002 at 01:24:36PM +0100, Sander Striker wrote:
Hi,
The 'high free' patch. I'm not sure we want this. It may hide pools abuse problems.
Yeah, I agree we don't really want this. If we run out of memory with the normal pools, it means that the lifetimes are most likely incorrect.
But, perhaps this could be a #define with a debug option? -- justin
We definitely don't want this IMHO. If the pools are filling up, then either pools are the incorrect model for your app, or they aren't being cleared often enough. I would much rather not have this as an option at all, because that just encourages people to use it. :-)
Ryan
It is the memory on the freelists that grows without bounds. The patch free()s memory that is added to a freelist when the freelist already holds a certain amount of free memory. This is very usefull when you have peak memory usage as some people pointed out.
The pools model is something you are stuck with it if you want to use APR. And it is not always pools abuse which gives you big chunks of mem on the freelist. Although I must admit that I would recommend some serious review of the code which shows this behaviour.
Anyhow, I'd like to add a configure option which you can feed the amount of memory you want as a maximum on a freelist, defaulting to infinite.
Thoughts?
I like the idea of a configurable maximum. It probably should be run-time configurable rather than build-time configurable, though. It would be even better if the max free list size could be specified on a per-allocator basis, so that the application developer could tailor the properties of each free list to the needs of the app.
--Brian
