linux-kernel - Re: Memory management issue in 4.18.15

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20181022234425.GA18716@tower.DHCP.thefacebook.com>
Date:   Mon, 22 Oct 2018 23:44:33 +0000
From:   Roman Gushchin <guro@...com>
To:     Spock <dairinin@...il.com>
CC:     Spock <dairinin@...il.com>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Rik van Riel <riel@...riel.com>,
        "Johannes Weiner" <hannes@...xchg.org>,
        Vladimir Davydov <vdavydov.dev@...il.com>,
        Shakeel Butt <shakeelb@...gle.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Sasha Levin <alexander.levin@...rosoft.com>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "linux-mm@...ck.org" <linux-mm@...ck.org>
Subject: Re: Memory management issue in 4.18.15

> On Sat 20-10-18 14:41:40, Spock wrote:
> > Hello,
> > 
> > I have a workload, which creates lots of cache pages. Before 4.18.15,
> > the behavior was very stable: pagecache is constantly growing until it
> > consumes all the free memory, and then kswapd is balancing it around
> > low watermark. After 4.18.15, once in a while khugepaged is waking up
> > and reclaims almost all the pages from pagecache, so there is always
> > around 2G of 8G unused. THP is enabled only for madvise case and are
> > not used.

Spock, can you, please, check if the following patch solves the problem
for you?

Thank you!

--

diff --git a/fs/inode.c b/fs/inode.c
index 73432e64f874..63aca301a8bc 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -731,7 +731,7 @@ static enum lru_status inode_lru_isolate(struct list_head *item,
        }
 
        /* recently referenced inodes get one more pass */
-       if (inode->i_state & I_REFERENCED) {
+       if (inode->i_state & I_REFERENCED || inode->i_data.nrpages > 1) {
                inode->i_state &= ~I_REFERENCED;
                spin_unlock(&inode->i_lock);
                return LRU_ROTATE;