On Mon, Sep 19, 2005 at 04:31:02PM +1000, Nick Piggin wrote:
> On Sun, 2005-09-18 at 17:35 +0300, Dan Aloni wrote:
> > Hello,
> >
> > Is there currently a workaround available for handling large MTU
> > (larger than 1 page, even 2-order) in the Linux network stack?
> >
> > The problem with large MTU is external memory fragmentation in
> > the buddy system following high workload, causing alloc_skb() to
> > fail.
> >
> > I'm interested in patches for both 2.4 and 2.6 kernels.
> >
>
> Yes there is currently a workaround. That is to keep increasing
> /proc/sys/vm/min_free_kbytes until your allocation failures stop.
We have developed a much more reliable workaround which works on both
the 2.4 and 2.6 trees.
Our development is called 'Pre-allocated Big Buffers', basically prebb
provides fixed-sized pools of fixed-size blocks that are allocated during
boot time using the bootmem allocator (thus are disconnected from the
slab cache completely). block size need not to be page aligned. It is
possible to allocate these blocks at O(1) efficiency at any context.
Each pool has a minimum and maximum object size (where allocations
should strive to be the maximum for memory usage efficiency). Currently
we use prebb to ensure no fragmentation and fine-tuned memory usage.
(Of course a few changes inside net/core/skbuff.c were needed for
skb buffers to allocate from prebb instead of slab).
--
Dan Aloni
[email protected], [email protected], [email protected]
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
| |
 |