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Questions under category : Linux on z » Memory
 
 
Q : Why is memory sizing so important for a Linux virtual machine on System z?
A : Memory sizing for linux virtual machines on System z is an important task for optimizing memory usage. z/VM supports the sharing of physical resources to a very high degree. Many virtual machines compete for real memory. Therefore sizing memory for a linux workload is a critical success factor. In a z/VM system the optimal size of a linux virtual machine is typically lower than that of the same workload on a physical server. Linux will satisfy itsí kernel and application memory requirements, and carve up the rest for i/o buffers and file caching. This has been linuxes traditional approach. In the highly shared environment like z/VM ratcheting down memory size is a successful strategy. A good starting point is to decrease memory until linux swapping occurs. Then by careful monitoring and tweaking you can find the sweet spot of virtual machine memory size.
Posted : Marc on   February 12, 2009 at 03:20 pm
Memory sizing for linux virtual machines on System z is an important task for optimizing memory usage. z/VM supports the sharing of physical resources to a very high degree. Many virtual machines compete for real memory. Therefore sizing memory for a linux workload is a critical success factor. In a z/VM system the optimal size of a linux virtual machine is typically lower than that of the same workload on a physical server. Linux will satisfy itsí kernel and application memory requirements, and carve up the rest for i/o buffers and file caching. This has been linuxes traditional approach. In the highly shared environment like z/VM ratcheting down memory size is a successful strategy. A good starting point is to decrease memory until linux swapping occurs. Then by careful monitoring and tweaking you can find the sweet spot of virtual machine memory size.
 
 
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Memory sizing for linux virtual machines on System z is an important task for optimizing memory usage.  z/VM supports the sharing of physical resources to a very high degree. Many virtual machines compete for real memory.  Therefore sizing memory for a linux workload is a critical success factor.

 

In a z/VM system the optimal size of a linux virtual machine is typically lower than that of the same workload on a physical server.  Linux will satisfy itsí kernel and application memory requirements, and carve up the rest for i/o buffers and file caching.  This has been linuxes traditional approach.

 

In the highly shared environment like z/VM ratcheting down memory size is a successful strategy. A good starting point is to decrease memory until linux swapping occurs.  Then by careful monitoring and tweaking you can find the sweet spot of virtual machine memory size.

 
 
Posted : Donna on  February 20, 2009 at 05:46 pm

Memory sizing for linux virtual machines on System z is an important task for optimizing memory usage.  z/VM supports the sharing of physical resources to a very high degree. Many virtual machines compete for real memory.  Therefore sizing memory for a linux workload is a critical success factor.

 

In a z/VM system the optimal size of a linux virtual machine is typically lower than that of the same workload on a physical server.  Linux will satisfy itsí kernel and application memory requirements, and carve up the rest for i/o buffers and file caching.  This has been linuxes traditional approach.

 

In the highly shared environment like z/VM ratcheting down memory size is a successful strategy. A good starting point is to decrease memory until linux swapping occurs.  Then by careful monitoring and tweaking you can find the sweet spot of virtual machine memory size.

 
 
 
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