diff options
Diffstat (limited to 'target/linux/s3c24xx/patches-2.6.24/1316-jffs2-choke-gc-thread.patch.patch')
| -rw-r--r-- | target/linux/s3c24xx/patches-2.6.24/1316-jffs2-choke-gc-thread.patch.patch | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/target/linux/s3c24xx/patches-2.6.24/1316-jffs2-choke-gc-thread.patch.patch b/target/linux/s3c24xx/patches-2.6.24/1316-jffs2-choke-gc-thread.patch.patch new file mode 100644 index 000000000..b3d5c0cbd --- /dev/null +++ b/target/linux/s3c24xx/patches-2.6.24/1316-jffs2-choke-gc-thread.patch.patch @@ -0,0 +1,55 @@ +From 9706327002caebe6633c93e605882ea37172ec57 Mon Sep 17 00:00:00 2001 +From: Andres Salomon <dilinger@debian.org> +Date: Mon, 3 Nov 2008 01:08:25 +0000 +Subject: [PATCH] jffs2-choke-gc-thread.patch + +I've noticed some pretty poor behavior on OLPC machines after bootup, when +gdm/X are starting. The GCD monopolizes the scheduler (which in turns means +it gets to do more nand i/o), which results in processes taking much much +longer than they should to start. + +As an example, on an OLPC machine going from OFW to a usable X (via auto-login +gdm) takes 2m 30s. The majority of this time is consumed by the switch into +graphical mode. With this patch, we cut a full 60s off of bootup time. After +bootup, things are much snappier as well. + +Note that we have seen a CRC node error with this patch that causes the machine +to fail to boot, but we've also seen that problem without this patch. + +Signed-off-by: Andres Salomon <dilinger@debian.org> +--- + fs/jffs2/background.c | 18 +++++++++++------- + 1 files changed, 11 insertions(+), 7 deletions(-) + +diff --git a/fs/jffs2/background.c b/fs/jffs2/background.c +index 8adebd3..f38d557 100644 +--- a/fs/jffs2/background.c ++++ b/fs/jffs2/background.c +@@ -95,13 +95,17 @@ static int jffs2_garbage_collect_thread(void *_c) + schedule(); + } + +- /* This thread is purely an optimisation. But if it runs when +- other things could be running, it actually makes things a +- lot worse. Use yield() and put it at the back of the runqueue +- every time. Especially during boot, pulling an inode in +- with read_inode() is much preferable to having the GC thread +- get there first. */ +- yield(); ++ /* Problem - immediately after bootup, the GCD spends a lot ++ * of time in places like jffs2_kill_fragtree(); so much so ++ * that userspace processes (like gdm and X) are starved ++ * despite plenty of cond_resched()s and renicing. Yield() ++ * doesn't help, either (presumably because userspace and GCD ++ * are generally competing for a higher latency resource - ++ * disk). ++ * This forces the GCD to slow the hell down. Pulling an ++ * inode in with read_inode() is much preferable to having ++ * the GC thread get there first. */ ++ schedule_timeout_interruptible(msecs_to_jiffies(50)); + + /* Put_super will send a SIGKILL and then wait on the sem. + */ +-- +1.5.6.5 + |