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
| ||
|
Date: Mon, 13 Jun 2016 13:42:37 +0900 From: Minchan Kim <minchan@...nel.org> To: Ganesh Mahendran <opensource.ganesh@...il.com> CC: Linux-MM <linux-mm@...ck.org>, linux-kernel <linux-kernel@...r.kernel.org>, Andrew Morton <akpm@...ux-foundation.org>, Nitin Gupta <ngupta@...are.org>, Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>, <rostedt@...dmis.org>, <mingo@...hat.com> Subject: Re: [PATCH] mm/zsmalloc: add trace events for zs_compact On Wed, Jun 08, 2016 at 02:39:19PM +0800, Ganesh Mahendran wrote: <snip> > zsmalloc is not only used by zram, but also zswap. Maybe > others in the future. > > I tried to use function_graph. It seems there are too much log > printed: > ------ > root@...-test:/sys/kernel/debug/tracing# cat trace > # tracer: function_graph > # > # CPU DURATION FUNCTION CALLS > # | | | | | | | > 2) | zs_compact [zsmalloc]() { > 2) | /* zsmalloc_compact_start: pool zram0 */ > 2) 0.889 us | _raw_spin_lock(); > 2) 0.896 us | isolate_zspage [zsmalloc](); > 2) 0.938 us | _raw_spin_lock(); > 2) 0.875 us | isolate_zspage [zsmalloc](); > 2) 0.942 us | _raw_spin_lock(); > 2) 0.962 us | isolate_zspage [zsmalloc](); > ... > 2) 0.879 us | insert_zspage [zsmalloc](); > 2) 4.520 us | } > 2) 0.975 us | _raw_spin_lock(); > 2) 0.890 us | isolate_zspage [zsmalloc](); > 2) 0.882 us | _raw_spin_lock(); > 2) 0.894 us | isolate_zspage [zsmalloc](); > 2) | /* zsmalloc_compact_end: pool zram0: 0 pages > compacted(total 0) */ > 2) # 1351.241 us | } > ------ > => 1351.241 us used > > And it seems the overhead of function_graph is bigger than trace event. > > bash-3682 [002] .... 1439.180646: zsmalloc_compact_start: pool zram0 > bash-3682 [002] .... 1439.180659: zsmalloc_compact_end: pool zram0: > 0 pages compacted(total 0) > => 13 us > 1351.241 us You could use set_ftrace_filter to cut out. To introduce new event trace to get a elasped time, it's pointless, I think. It should have more like pool name you mentioned. Like saying other thread, It would be better to show [pool name, compact size_class, the number of object moved, the number of freed page], IMO. Thanks.
Powered by blists - more mailing lists