Review request for 5049299 (original) (raw)

Florian Weimer fweimer at bfk.de
Fri May 29 10:47:06 UTC 2009

Florian Weimer wrote:

* Andrew Haley:

The latter leads to problems if the maximum heap size is relatively large. Currently, -Xmx is reserved, and some software fails to build on vm.overcommitmemory systems due to this. I don't get it. Why would overcommit cause some software to fail to build? I can understand it failing if overcommit was turned off. Sorry, I meant to write "vm.overcommitmemory=2". Well, the system is doing what the user asked it to do. -Xmx means "please reserve this memory for me, Hal"; if the memory isn't there, then it's surely quite reasonable for Hal to respond "I'm sorry Dave, I can't do that."

Well, I thought -Xms means that. An untuned VM is not expected to hit the -Xmx limit. At least this is what I see in practice, and to me this is the distinction expressed between the -Xmx and -Xms flags.

Reserving the -Xms heap portion does make sense, though.

-- Florian Weimer <fweimer at bfk.de> BFK edv-consulting GmbH http://www.bfk.de/ Kriegsstraße 100 tel: +49-721-96201-1 D-76133 Karlsruhe fax: +49-721-96201-99

More information about the core-libs-dev mailing list