(2013/04/11 23:47), Naoya Horiguchi wrote: > On Thu, Apr 11, 2013 at 04:00:12PM +0200, Andi Kleen wrote: >>> I don't think it's enough to do ratelimit only for me_pagecache_dirty(). >>> When tons of memory errors flood, all of printk()s in memory error handler >>> can print out tons of messages. >> >> Note that when you really have a flood of uncorrected errors you'll >> likely die soon anyways as something unrecoverable is very likely to >> happen. Error memory recovery cannot fix large scale memory corruptions, >> just the rare events that slip through all the other memory error correction >> schemes. >> >> So I wouldn't worry too much about that. > > I agree. > My previous comment is valid only when we assume the flooding can happen > (and I personally don't believe that can happen except for in testing.) > > And for paranoid users, we can suggest that they set up mcelog script > triggering to turn off vm.memory_failure_recovery when memory errors flood. > Such users don't expect that memory error handling works fine in flooding, > so just suppressing kernel messages is pointless. > > Thanks, > Naoya Hi Andi, Horiguchi-san, Kosaki-san Thank you for your comments. I agree with your opinions. I think that occurrence of uncorrected error is rare event, too. I introduced a limitation feature using ratelimit in my patch in honor of the previous discussion a half year ago. In the discussion, Andrew-san threw a concern of a flood of uncorrected error for the patch proposed by Horiguchi-san. I think that ratelimit can be removed to output all "important messages". I will try to resend patches sepalately, one is for outputting error messages related to a corrupted file and the other is for adding a panic knob to handle data lost of dirty cache which is caused by both memory error and I/O error. Regards, Mitsuhiro Tanino -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>