FM / memory

/usr/share/systemtap/examples/memory

Name	Size	Mode	Actions
cachestat.meta	545	0644	edit dl rm
cachestat.stp	1318	0755	edit dl rm
glibc-malloc.meta	381	0644	edit dl rm
glibc-malloc.stp	2486	0755	edit dl rm
hugepage_clear_delays.meta	946	0644	edit dl rm
hugepage_clear_delays.stp	483	0755	edit dl rm
hugepage_collapse.meta	718	0644	edit dl rm
hugepage_collapse.stp	159	0755	edit dl rm
hugepage_cow_delays.meta	1106	0644	edit dl rm
hugepage_cow_delays.stp	475	0755	edit dl rm
hugepage_split.meta	756	0644	edit dl rm
hugepage_split.stp	153	0755	edit dl rm
hw_watch_addr.meta	787	0644	edit dl rm
hw_watch_addr.stp	167	0755	edit dl rm
hw_watch_addr.tcl	97	0644	edit dl rm
hw_watch_sym.meta	715	0644	edit dl rm
hw_watch_sym.stp	167	0755	edit dl rm
hw_watch_sym.tcl	97	0644	edit dl rm
kmalloc-top	3888	0755	edit dl rm
kmalloc-top.meta	695	0644	edit dl rm
last_100_frees.meta	420	0644	edit dl rm
last_100_frees.stp	803	0755	edit dl rm
last_100_frees.tcl	79	0644	edit dl rm
last_100_frees.txt	774	0644	edit dl rm
mmanonpage.meta	1225	0644	edit dl rm
mmanonpage.stp	1816	0755	edit dl rm
mmfilepage.meta	1033	0644	edit dl rm
mmfilepage.stp	3537	0755	edit dl rm
mmreclaim.meta	606	0644	edit dl rm
mmreclaim.stp	5232	0755	edit dl rm
mmwriteback.meta	1114	0644	edit dl rm
mmwriteback.stp	1900	0755	edit dl rm
numa_faults.meta	702	0644	edit dl rm
numa_faults.stp	973	0755	edit dl rm
numa_faults.txt	1710	0644	edit dl rm
overcommit.meta	584	0644	edit dl rm
overcommit.stp	217	0755	edit dl rm
pfaults.meta	744	0644	edit dl rm
pfaults.stp	875	0755	edit dl rm
pfaults.txt	558	0644	edit dl rm
vm.tracepoints.meta	608	0644	edit dl rm
vm.tracepoints.stp	414	0755	edit dl rm
vm.tracepoints.txt	557	0644	edit dl rm

Edit: /usr/share/systemtap/examples/memory/hugepage_cow_delays.meta (1106B)

title: Summarize the time each process spends doing copy on write for huge pages
name: hugepage_cow_delays.stp
version: 1.0
author: William Cohen
keywords: memory
subsystem: memory
status: production
exit: user-controlled
output: sorted-list
scope: system-wide
description: The system may attempt to reduce memory use by having two or more difference processes share the same writeable page in memory.  However, when one of the processes write to shared page that is marked copy on write (COW) the page must be duplicated and then modified.  On x86_64 machines the huge pages are 2MB in size, 512 times larger than a normal 4KB page.  Thus, copy on write operation on a huge page can delay program execution by a hundred or more microseconds and maybe noticeable to latency sensitive programs.  This script will tally the number of times that each process triggers a huge page copy on write, the total time in microseconds spent copying the pages, and the average time in microseconds of the huge page copy.
test_check: stap -p4 hugepage_cow_delays.stp
test_installcheck: stap hugepage_cow_delays.stp -T 1

title: Summarize the time each process spends doing copy on write for huge pages name: hugepage_cow_delays.stp version: 1.0 author: William Cohen keywords: memory subsystem: memory status: production exit: user-controlled output: sorted-list scope: system-wide description: The system may attempt to reduce memory use by having two or more difference processes share the same writeable page in memory. However, when one of the processes write to shared page that is marked copy on write (COW) the page must be duplicated and then modified. On x86_64 machines the huge pages are 2MB in size, 512 times larger than a normal 4KB page. Thus, copy on write operation on a huge page can delay program execution by a hundred or more microseconds and maybe noticeable to latency sensitive programs. This script will tally the number of times that each process triggers a huge page copy on write, the total time in microseconds spent copying the pages, and the average time in microseconds of the huge page copy. test_check: stap -p4 hugepage_cow_delays.stp test_installcheck: stap hugepage_cow_delays.stp -T 1