/usr/share/systemtap/examples/memory
Edit: /usr/share/systemtap/examples/memory/mmfilepage.stp (3537B)
#!/usr/bin/stap
#
# Note that there are 2 sets of filemap kernel tracepoints:
#
# - older kernels RHEL5 (2.6.18) - RHEL6 (2.6.32): mm_filemap_fault,
# mm_filemap_cow, mm_filemap_unmap mm_filemap_userunmap
# - newer kernels: mm_filemap_add_to_page_cache,
# mm_filemap_delete_from_page_cache
#
# This script attempts to handle them both.
global traced_pid, command
global allocation, free
global old_set_hits
global file_fault, file_cow, file_uunmap, file_kunmap
global file_page_cache_add, file_page_cache_delete
function log_event:long ()
{
return (!traced_pid || traced_pid == pid())
}
probe kernel.{trace("mm_page_alloc")!, trace("mm_page_allocation")} {
if (!log_event()) next
allocation[pid()] <<< 1
command[pid()] = execname()
}
probe kernel.{trace("mm_page_free")!, trace("mm_page_free_direct")} {
if (!log_event()) next
free[pid()] <<< 1
}
probe kernel.trace("mm_filemap_fault")? {
if (!log_event()) next
old_set_hits <<< 1
file_fault[pid()] <<< 1
}
probe kernel.trace("mm_filemap_cow")? {
if (!log_event()) next
old_set_hits <<< 1
file_cow[pid()] <<< 1
}
probe kernel.trace("mm_filemap_unmap")? {
if (!log_event()) next
old_set_hits <<< 1
file_kunmap[pid()] <<< 1
}
probe kernel.trace("mm_filemap_userunmap")? {
if (!log_event()) next
old_set_hits <<< 1
file_uunmap[pid()] <<< 1
}
probe kernel.trace("mm_filemap_add_to_page_cache")? {
if (!log_event()) next
file_page_cache_add[pid()] <<< 1
}
probe kernel.trace("mm_filemap_delete_from_page_cache")? {
if (!log_event()) next
file_page_cache_delete[pid()] <<< 1
}
probe never {
# Do a few initializations to let stap know what the global
# variable types are. Note that since we're in a "never"
# probe, these initializations will never actually happen.
traced_pid = 0
old_set_hits <<< 1
file_fault[0] <<< 1
file_cow[0] <<< 1
file_uunmap[0] <<< 1
file_kunmap[0] <<< 1
file_page_cache_add[0] <<< 1
file_page_cache_delete[0] <<< 1
}
probe begin {
printf("Starting data collection\n")
if (target())
printf("mode Specific Pid, traced pid: %d\n\n", target())
else
printf("mode - All Pids\n\n")
}
function print_old_format:long ()
{
printf("Command Pid Alloc Free F_fault F_cow F_kunmap F_uunmap\n")
printf("------- --- ----- ---- ------- ----- -------- --------\n")
foreach (pid+ in allocation) {
printf("%-16s %10d %9d %9d %8d %8d %8d %8d\n",
command[pid], pid,
@count(allocation[pid]), @count(free[pid]),
@count(file_fault[pid]), @count(file_cow[pid]),
@count(file_kunmap[pid]), @count(file_uunmap[pid]))
}
}
function print_new_format:long ()
{
printf("Command Pid Alloc Free CacheAdd CacheDel\n")
printf("------- --- ----- ---- -------- --------\n")
foreach (pid+ in allocation) {
printf("%-16s %10d %9d %9d %8d %8d\n",
command[pid], pid,
@count(allocation[pid]), @count(free[pid]),
@count(file_page_cache_add[pid]),
@count(file_page_cache_delete[pid]))
}
}
probe end {
printf("Terminating data collection\n")
# We'll either have hits from the old set of filemap tracepoints
# (mm_filemap_fault, mm_filemap_cow, mm_filemap_unmap,
# mm_filemap_userunmap) or the new set of filemap tracepoints
# (mm_filemap_add_to_page_cache,
# mm_filemap_delete_from_page_cache). Print out the set that got
# hits.
if (@count(old_set_hits))
print_old_format()
else
print_new_format()
}