On Sat, 05 Aug 2000, Benno Senoner wrote:
hmmm .. I looked at the source and seems that I can answer this question by
myself:
>
> Now my question: is this more than 128MB mlock() problem a limitation of the
> 2.2.x kernel or can it be lifted by some sysctl ?
Yes, see mm/mlock.c
-----
/* we may lock at most half of physical memory... */
/* (this check is pretty bogus, but doesn't hurt) */
if (locked > num_physpages/2)
goto out;
-----
Argh ! this is bogus ! , on my 250MB RAM BOX , I want to be able to mlock at
least something like 200-220MB ,
What is the purpose of this artificial limitation ?
I agree that running out of phys pages is bad, but with those big mem sizes like
256-512MB, a margin of 30-50MB (configurable) should be enough.
Can we make this configurable via sysctl in 2.4 ?
(without this realtime multimedia apps will be unable to take advantage of the
full amount of RAM, because swappable mem is useless in certain cases)
>
> Does kernel 2.4 have the same limitiation ?
Yes :-(
same code present in 2.4-test6-pre2.
But I was really wondering : am I the only one that needs more than
ramsize/2 mlocked() mem in a single process ?
hopefully not ...
let me know
thanks,
Benno.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sat Aug 05 2000 - 11:54:55 EDT