Re: [PATCH] net: skbuff: allocate the fclone in the current NUMA node

[Shijie Huang]

在 2024/2/20 16:17, Eric Dumazet 写道:
> On Tue, Feb 20, 2024 at 7:26 AM Shijie Huang
> <shijie@xxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:
> > 在 2024/2/20 13:32, Eric Dumazet 写道:
> > > On Tue, Feb 20, 2024 at 3:18 AM Huang Shijie
> > > <shijie@xxxxxxxxxxxxxxxxxxxxxx> wrote:
> > > > The current code passes NUMA_NO_NODE to __alloc_skb(), we found
> > > > it may creates fclone SKB in remote NUMA node.
> > > This is intended (WAI)
> > Okay. thanks a lot.
> >
> > It seems I should fix the issue in other code, not the networking.
> >
> > > What about the NUMA policies of the current thread ?
> > We use "numactl -m 0" for memcached, the NUMA policy should allocate
> > fclone in
> >
> > node 0, but we can see many fclones were allocated in node 1.
> >
> > We have enough memory to allocate these fclones in node 0.
> >
> > > Has NUMA_NO_NODE behavior changed recently?
> > I guess not.
> > > What means : "it may creates" ? Please be more specific.
> > When we use the memcached for testing in NUMA, there are maybe 20% ~ 30%
> > fclones were allocated in
> >
> > remote NUMA node.
> Interesting, how was it measured exactly ?

I created a private patch to record the status for each fclone allocation.


> Are you using SLUB or SLAB ?

I think I use SLUB. (CONFIG_SLUB=y, 
CONFIG_SLAB_MERGE_DEFAULT=y,CONFIG_SLUB_CPU_PARTIAL=y)


Thanks

Huang Shijie