diff options
Diffstat (limited to 'Documentation/sysctl')
| -rw-r--r-- | Documentation/sysctl/kernel.txt | 14 | ||||
| -rw-r--r-- | Documentation/sysctl/vm.txt | 14 |
2 files changed, 28 insertions, 0 deletions
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt index daabdd7ee543..a3683ce2a2f3 100644 --- a/Documentation/sysctl/kernel.txt +++ b/Documentation/sysctl/kernel.txt @@ -61,6 +61,7 @@ show up in /proc/sys/kernel: - perf_cpu_time_max_percent - perf_event_paranoid - perf_event_max_stack +- perf_event_max_contexts_per_stack - pid_max - powersave-nap [ PPC only ] - printk @@ -668,6 +669,19 @@ The default value is 127. ============================================================== +perf_event_max_contexts_per_stack: + +Controls maximum number of stack frame context entries for +(attr.sample_type & PERF_SAMPLE_CALLCHAIN) configured events, for +instance, when using 'perf record -g' or 'perf trace --call-graph fp'. + +This can only be done when no events are in use that have callchains +enabled, otherwise writing to this file will return -EBUSY. + +The default value is 8. + +============================================================== + pid_max: PID allocation wrap value. When the kernel's next PID value diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index 34a5fece3121..720355cbdf45 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -57,6 +57,7 @@ Currently, these files are in /proc/sys/vm: - panic_on_oom - percpu_pagelist_fraction - stat_interval +- stat_refresh - swappiness - user_reserve_kbytes - vfs_cache_pressure @@ -755,6 +756,19 @@ is 1 second. ============================================================== +stat_refresh + +Any read or write (by root only) flushes all the per-cpu vm statistics +into their global totals, for more accurate reports when testing +e.g. cat /proc/sys/vm/stat_refresh /proc/meminfo + +As a side-effect, it also checks for negative totals (elsewhere reported +as 0) and "fails" with EINVAL if any are found, with a warning in dmesg. +(At time of writing, a few stats are known sometimes to be found negative, +with no ill effects: errors and warnings on these stats are suppressed.) + +============================================================== + swappiness This control is used to define how aggressive the kernel will swap |