rsshogfrac

Description

The number of physical memory pages occupied by a process at any given time is called its resident set size (RSS). The limit to the RSS of a process is determined by its allowable memory-use resource limit. rsshogfrac is designed to guarantee that even if one or more processes are exceeding their RSS limit, some percentage of memory is always kept free so that good interactive response is maintained.

Processes are permitted to exceed their RSS limit until either:

• one or more processes exceed their default RSS limit (thereby becoming an ''RSS hog'') and the amount of free memory drops below rsshogfrac of the total amount of physical memory; or

• the amount of free memory drops below GPGSHI

  In either of these cases, the paging daemon runs and trims pages from all RSS processes exceeding the RSS limit.

  The parameter RSSHOGFRAC is expressed as a fraction of the total physical memory of the system. The default value is 75 percent.

  This parameter is specified in /var/sysgen/mtune. For more information, see the gpgshi, gpgslo, and rsshogslop resource limits.

Value

Default: 75% of total memory

Range: 0-100% of total memory

When to Change

The default value is adequate for most systems.