Happy new year, guys. On Wed, Dec 28, 2011 at 01:19:18PM -0800, Tejun Heo wrote: > > On Wed, Dec 28, 2011 at 9:50 AM, Hugh Dickins <hughd@xxxxxxxxxx> wrote: > > > "It's the tmpfs swapping test that I've been running, with variations, > > > for years. System booted with mem=700M and 1.5G swap, two repetitious > > > make -j20 kernel builds (of a 2.6.24 kernel: I stuck with that because > > > the balance of built to unbuilt source grows smaller with later kernels), > > > one directly in a tmpfs, the other in a 1k-block ext2 (that I drive with > > > ext4's CONFIG_EXT4_USE_FOR_EXT23) on /dev/loop0 on a 450MB tmpfs file." > > > > > > I doubt much of that (quoted from an older mail to someone else about > > > one of the many other bugs it's found) is relevant: maybe just plenty > > > of file I/O and swapping. > > > > Plain -j4 build isn't triggering anything. I'll try to replicate the condition. > > It's not too reliable but I can reproduce it with -j 22 allmodconfig > build inside qemu w/ 512M of memory. I'll try to find out what's > going on. I misread the code, the problem is empty cfqq on the cfq prio tree. I don't think this is caused by recent io_context changes. It looks like somebody is forgetting to remove cfqq from the dispatch prio tree after emptying a cfqq by removing a request from it. Jens, any ideas? Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-next" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
