Messages in this thread | | | Date | Tue, 26 Apr 2011 12:47:43 -0700 | From | Andrew Morton <> | Subject | Re: readahead and oom |
| |
On Tue, 26 Apr 2011 17:20:29 +0800 Wu Fengguang <fengguang.wu@intel.com> wrote:
> Pass __GFP_NORETRY|__GFP_NOWARN for readahead page allocations. > > readahead page allocations are completely optional. They are OK to > fail and in particular shall not trigger OOM on themselves.
I have distinct recollections of trying this many years ago, finding that it caused problems then deciding not to do it. But I can't find an email trail and I don't remember the reasons :(
If the system is so stressed for memory that the oom-killer might get involved then the readahead pages may well be getting reclaimed before the application actually gets to use them. But that's just an aside.
Ho hum. The patch *seems* good (as it did 5-10 years ago ;)) but there may be surprising side-effects which could be exposed under heavy testing. Testing which I'm sure hasn't been performed...
| |