Subject: Re: [PATCH] neighbour.c: Avoid GC directly after state change

From: YOSHIFUJI Hideaki <[email-masked]>
Date: Tue, 21 Apr 2015 12:58:56 +0900

Ulf Samuelsson wrote:
>> How many neighbors do you want to maintain?
>> I guess you have to increase the number of gc_thresh1.
> The current use cases have up to 2048 entries.
> This is expected to grow in the future.
> The 3.4 kernel used in the system today is limited to 1024,
> but that has been raised to about 10k.
> 
> The gc_thresh1 test is not implemented in 3.4 but can be backported,
> but still not convinced it is a good idea.

Why?

> To complicate things, one requirement is that for some interfaces
> you always want to keep things alive, if connected, but
> for other interfaces you want things to be removed
> to conserve memory.
> Actually you would want to do this selection on a subnet level.

If you want to introduce per-interface parameter, I am okay with it.

> 
> Internal discussions resulted in a proposal to change the patch,
> so that you have a "keepalive" flag which is tested after
> it has been decided to exit the REACHABLE state.
> 
> if the "keepalive" flag is set, you always go to DELAY state from REACHABLE.

No.

-- 
Hideaki Yoshifuji <[email-masked]>
Technical Division, MIRACLE LINUX CORPORATION