- can decrease its frequency by writing a large value to
- /proc/sys/vm/stat_interval. The default value is HZ,
- for an interval of one second. Of course, larger values
- will make your virtual-memory statistics update more
- slowly. Of course, you can also run your workload at
- a real-time priority, thus preempting vmstat_update().
+ can decrease its frequency by writing a large value
+ to /proc/sys/vm/stat_interval. The default value is
+ HZ, for an interval of one second. Of course, larger
+ values will make your virtual-memory statistics update
+ more slowly. Of course, you can also run your workload
+ at a real-time priority, thus preempting vmstat_update(),
+ but if your workload is CPU-bound, this is a bad idea.
+ However, there is an RFC patch from Christoph Lameter
+ (based on an earlier one from Gilad Ben-Yossef) that
+ reduces or even eliminates vmstat overhead for some
+ workloads at https://lkml.org/lkml/2013/9/4/379.