From mboxrd@z Thu Jan 1 00:00:00 1970 From: kosaki.motohiro@jp.fujitsu.com (KOSAKI Motohiro) Date: Thu, 29 Jan 2009 12:42:55 +0900 (JST) Subject: [ltt-dev] LTTng 0.87 improved page fault tracing In-Reply-To: <20090127210203.GA13478@Krystal> References: <20090127210203.GA13478@Krystal> Message-ID: <20090129123827.A959.KOSAKI.MOTOHIRO@jp.fujitsu.com> Hi interesting.. > I just combined the 4 page fault handler events that were in the tracing > hot path of LTTng into 2 : > > kernel page_fault_entry > kernel page_fault_exit > > They take as parameter the combination of what was available in the > trap_entry/exit events and handle_mm_fault entry/exit events. This > should lessen the performance impact of the tracer when it's active. > I did the related modifications in LTTV 0.12.8. Just question. As far as I know, customer has two different requeremtn of the page fault. (1) collect number of all page fault -> if it is too large, too many interrupt decrease performance. (2) collect number of major page fault -> major page fault indicate to increase random access I/O, then, some customer want to collect major page fault (don't include minor page fault) Is this patch fill (2) requirement?