Re: [PATCH] f2fs: set deadline to drop expired inmem pages
From: Chao Yu
Date: Tue Apr 10 2018 - 03:39:22 EST
Hi Jaegeuk,
On 2018/4/8 16:13, Chao Yu wrote:
> f2fs doesn't allow abuse on atomic write class interface, so except
> limiting in-mem pages' total memory usage capacity, we need to limit
> start-commit time as well, otherwise we may run into infinite loop
> during foreground GC because target blocks in victim segment are
> belong to atomic opened file for long time.
>
> Now, we will check the condition with f2fs_balance_fs_bg in
> background threads, once if user doesn't commit data exceeding 30
> seconds, we will drop all cached data, so I expect it can keep our
> system running safely to prevent Dos attack.
Is it worth to add this patch to avoid abuse on atomic write interface by user?
Thanks,