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M4T
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High RAM usage

Hi,

im having some high ram usage on one of my vm's its a "Guest -VM"  I have 6 blade servers but even if I move it to a different blade it still uses all 16GB ram im abit confused as the others don't,

ive also tried reinstalling the vm clean but it does the same unless its because its only DDR3 ram not DDR4 I believe its DDR3 1600mhz.

is there something missing orr.

Matt

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admin
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Solutions for Memory Performance Problems

Host machine memory is the hardware backing for guest virtual memory and guest physical memory. Host machine memory must be at least slightly larger than the combined active memory of the virtual machines on the host. A virtual machine's memory size must be slightly larger than the average guest memory usage. Increasing the virtual machine memory size results in more overhead memory usage.

Problem

■Memory usage is constantly high (94% or greater) or constantly low (24% or less).

■Free memory consistently is 6% or less and swapping frequently occurs.

Cause

■The host probably is lacking the memory required to meet the demand. The active memory size is the same as the granted memory size, which results in memory resources that are not sufficient for the workload. Granted memory is too much if the active memory is constantly low.

■Host machine memory resources are not enough to meet the demand, which leads to memory reclamation and degraded performance.

■The active memory size is the same as the granted memory size, which results in memory resources that are not sufficient for the workload.

Solution

■Verify that VMware Tools is installed on each virtual machine. The balloon driver is installed with VMware Tools and is critical to performance.

■Verify that the balloon driver is enabled. The VMkernel regularly reclaims unused virtual machine memory by ballooning and swapping. Generally, this does not impact virtual machine performance.

■Reduce the memory space on the virtual machine, and correct the cache size if it is too large. This frees up memory for other virtual machines.

■If the memory reservation of the virtual machine is set to a value much higher than its active memory, decrease the reservation setting so that the VMkernel can reclaim the idle memory for other virtual machines on the host.

■Migrate one or more virtual machines to a host in a DRS cluster.

■Add physical memory to the host.

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daphnissov
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"Guest -VM"

What do you mean by ""Guest -VM""?

Without knowing what that VM does and looking at specifics including its configuration, you don't provide much to go on.

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Gidrakos
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Also, what do you mean by "usage" ? Is the memory active or consumed? There's a difference.

Consumed is how much has been allocated to the VM, and active is how much is currently being used. Consumed will remain high until the OS sends the hypervisor a signal saying it can release the RAM, but if you're running a flavor of Linux, this call is never received by the hypervisor, and therefore RAM is never released even if it's not being used.

Is the underlying OS on the VM reporting that it's using all 16Gb? That's the best way to check it.

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M4T
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Hi,

1) Guest-VM is just the name of the virtual machine.

2) it is active RAM and the colour bar shows red, instead of green or amber.

Matt

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admin
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Solutions for Memory Performance Problems

Host machine memory is the hardware backing for guest virtual memory and guest physical memory. Host machine memory must be at least slightly larger than the combined active memory of the virtual machines on the host. A virtual machine's memory size must be slightly larger than the average guest memory usage. Increasing the virtual machine memory size results in more overhead memory usage.

Problem

■Memory usage is constantly high (94% or greater) or constantly low (24% or less).

■Free memory consistently is 6% or less and swapping frequently occurs.

Cause

■The host probably is lacking the memory required to meet the demand. The active memory size is the same as the granted memory size, which results in memory resources that are not sufficient for the workload. Granted memory is too much if the active memory is constantly low.

■Host machine memory resources are not enough to meet the demand, which leads to memory reclamation and degraded performance.

■The active memory size is the same as the granted memory size, which results in memory resources that are not sufficient for the workload.

Solution

■Verify that VMware Tools is installed on each virtual machine. The balloon driver is installed with VMware Tools and is critical to performance.

■Verify that the balloon driver is enabled. The VMkernel regularly reclaims unused virtual machine memory by ballooning and swapping. Generally, this does not impact virtual machine performance.

■Reduce the memory space on the virtual machine, and correct the cache size if it is too large. This frees up memory for other virtual machines.

■If the memory reservation of the virtual machine is set to a value much higher than its active memory, decrease the reservation setting so that the VMkernel can reclaim the idle memory for other virtual machines on the host.

■Migrate one or more virtual machines to a host in a DRS cluster.

■Add physical memory to the host.

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