Re: [PATCH] net: make SK_MEMORY_PCPU_RESERV tunable

To: Eric Dumazet <edumazet@xxxxxxxxxx>
Subject: Re: [PATCH] net: make SK_MEMORY_PCPU_RESERV tunable
From: "Lameter, Christopher" <cl@xxxxxxxxxxxxxxxxxxxxxx>
Date: Wed, 6 Mar 2024 09:01:15 -0800 (PST)
Cc: Adam Li <adamli@xxxxxxxxxxxxxxxxxxxxxx>, corbet@xxxxxxx, davem@xxxxxxxxxxxxx, kuba@xxxxxxxxxx, pabeni@xxxxxxxxxx, willemb@xxxxxxxxxx, yangtiezhu@xxxxxxxxxxx, atenart@xxxxxxxxxx, kuniyu@xxxxxxxxxx, wuyun.abel@xxxxxxxxxxxxx, leitao@xxxxxxxxxx, alexander@xxxxxxxxxxxxx, dhowells@xxxxxxxxxx, paulmck@xxxxxxxxxx, joel.granados@xxxxxxxxx, urezki@xxxxxxxxx, joel@xxxxxxxxxxxxxxxxx, linux-doc@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, netdev@xxxxxxxxxxxxxxx, patches@xxxxxxxxxxxxxxxxxxx, shijie@xxxxxxxxxxxxxxxxxxxxxx
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On Wed, 28 Feb 2024, Eric Dumazet wrote:

__sk_mem_raise_allocated() drops to 0.4%.


I suspect some kind of flow/cpu steering issues then.
Also maybe SO_RESERVE_MEM would be better for this workload.

This is via loopback. So there is a flow steering issue in the IPstack?

Follow-Ups:
- Re: [PATCH] net: make SK_MEMORY_PCPU_RESERV tunable
  - From: Eric Dumazet

References:
- [PATCH] net: make SK_MEMORY_PCPU_RESERV tunable
  - From: Adam Li
- Re: [PATCH] net: make SK_MEMORY_PCPU_RESERV tunable
  - From: Eric Dumazet
- Re: [PATCH] net: make SK_MEMORY_PCPU_RESERV tunable
  - From: Adam Li
- Re: [PATCH] net: make SK_MEMORY_PCPU_RESERV tunable
  - From: Eric Dumazet