From 9df04e1f25effde823a600e755b51475d438f56b Mon Sep 17 00:00:00 2001 From: Davide Libenzi Date: Thu, 29 Jan 2009 14:25:26 -0800 Subject: epoll: drop max_user_instances and rely only on max_user_watches Linus suggested to put limits where the money is, and max_user_watches already does that w/out the need of max_user_instances. That has the advantage to mitigate the potential DoS while allowing pretty generous default behavior. Allowing top 4% of low memory (per user) to be allocated in epoll watches, we have: LOMEM MAX_WATCHES (per user) 512MB ~178000 1GB ~356000 2GB ~712000 A box with 512MB of lomem, will meet some challenge in hitting 180K watches, socket buffers math teaches us. No more max_user_instances limits then. Signed-off-by: Davide Libenzi Cc: Willy Tarreau Cc: Michael Kerrisk Cc: Bron Gondwana Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux/sched.h') diff --git a/include/linux/sched.h b/include/linux/sched.h index 02e16d20730..5a7c7638873 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -630,7 +630,6 @@ struct user_struct { atomic_t inotify_devs; /* How many inotify devs does this user have opened? */ #endif #ifdef CONFIG_EPOLL - atomic_t epoll_devs; /* The number of epoll descriptors currently open */ atomic_t epoll_watches; /* The number of file descriptors currently watched */ #endif #ifdef CONFIG_POSIX_MQUEUE -- cgit v1.2.3-70-g09d2