Latest Posts



Translate

Total Pageviews

Monday, 23 March 2015

Advanced Memory Attributes

You can use the advanced memory attributes to customize memory resource usage.
Advanced Memory Attributes
Attribute
Description
Default
Mem.CtlMaxPercent
Limits the maximum amount of memory reclaimed from any virtual machine using vmmemctl, based on a percentage of its configured memory size. Specify 0 to disable reclamation using vmmemctl for all virtual machines.
65
Mem.ShareScanTime
Specifies the time, in minutes, within which an entire virtual machine is scanned for page sharing opportunities. Defaults to 60 minutes.
60
Mem.ShareScanGHz
Specifies the maximum amount of memory pages to scan (per second) for page sharing opportunities for each GHz of available host CPU resource.
Defaults to 4 MB/sec per 1GHz.
4
Mem.IdleTax
Specifies the idle memory tax rate, as a percentage. This tax effectively charges virtual machines more for idle memory than for memory they are actively using. A tax rate of 0 percent defines an allocation policy that ignores working sets and allocates memory strictly based on shares. A high tax rate results in an allocation policy that allows idle memory to be reallocated away from virtual machines that are unproductively hoarding it.
75
Mem.SamplePeriod
Specifies the periodic time interval, measured in seconds of the virtual machine’s execution time, over which memory activity is monitored to estimate working set sizes.
60
Mem.BalancePeriod
Specifies the periodic time interval, in seconds, for automatic memory reallocations. Significant changes in the amount of free memory also trigger reallocations.
15
Mem.AllocGuestLargePage
Set this option to 1 to enable backing of guest large pages with host large pages. Reduces TLB misses and improves performance in server workloads that use guest large pages. 0=disable.
1
Mem.AllocUsePSharePool
and
Mem.AllocUseGuestPool
Set these options to 1 to reduce memory fragmentation. If host memory is fragmented, the availability of host large pages is reduced. These options improve the probability of backing guest large pages with host large pages. 0 = disable.
1
Mem.MemZipEnable
Set this option to 1 to enable memory compression for the host. Set the option to 0 to disable memory compression.
1
Mem.MemZipMaxPct
Specifies the maximum size of the compression cache in terms of the maximum percentage of each virtual machine's memory that can be stored as compressed memory.
10
LPage.LPageDefragEnable
Set this option to 1 to enable large page defragmentation. 0 = disable.
1
LPage.LPageDefragRateVM
Maximum number of large page defragmentation attempts per second per virtual machine. Accepted values range from 1 to 1024.
32
LPage.LPageDefragRateTotal
Maximum number of large page defragmentation attempts per second. Accepted values range from 1 to 10240.
256
LPage.LPageAlwaysTryForNPT
Set this option to 1 to enable always try to allocate large pages for nested page tables (called 'RVI' by AMD or 'EPT' by Intel). 0= disable.
If you enable this option, all guest memory is backed with large pages in machines that use nested page tables (for example, AMD Barcelona). If NPT is not available, only some portion of guest memory is backed with large pages.
1

Source:-
VMware Documentation