Azure batch autoscale formula

Gal Hadar 5 Reputation points
2023-05-24T13:10:06.5166667+00:00

I'm trying to create a pool that always starts with 1 node. After 3 minutes of having more than 70% CPU usage the pool should generate another machine, and repeat. I'm using the current formula:

initialPoolSize = 1;
$TargetDedicatedNodes = initialPoolSize;
$totalDedicatedNodes =
    (avg($CPUPercent.GetSample(TimeInterval_Minute * 3)) >= 0.7) ?
    ($TargetDedicatedNodes + 1) : $TargetDedicatedNodes;

I also tried using this formula that is posted in the Microsoft documentation:

initialPoolSize = 1;
$TargetDedicatedNodes = initialPoolSize;
$totalDedicatedNodes =
    (min($CPUPercent.GetSample(TimeInterval_Minute * 3)) >= 0.7) ?
    ($CurrentDedicatedNodes * 1.1) : $CurrentDedicatedNodes;

Both formulas don't work, I'm stuck with only 1 node for the entire build time, and the CPU usage is at 100%.

If anyone has any experience with this and or can help that'll be greatly appreciated.

Azure Batch
Azure Batch
An Azure service that provides cloud-scale job scheduling and compute management.
308 questions
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  1. Gal Hadar 5 Reputation points
    2023-05-29T13:13:16.67+00:00

    This is the answer for anyone wondering

    maxNumberOfVMs = 20; // maximum number of VMs you want

    samplePercentThreshold = 0.7;

    sampleDuration = TimeInterval_Minute * 3;

    // Get the last sample

    $sample = (avg($CPUPercent.GetSample(sampleDuration)));

    // If the average CPU usage was more than 70%, increase nodes by one, if not true keeps as is

    $TargetDedicated = ($sample >= samplePercentThreshold ? $TargetDedicated +1 : $TargetDedicated);

    // If the average CPU usage is below 20% decrease nodes by one, if not true keep as is

    $TargetDedicated = ($sample <= 0.2 ? $TargetDedicated - 1 : $TargetDedicated);

    // Always keep the number of nodes under the maximum

    $TargetDedicated = min($TargetDedicated, maxNumberOfVMs);

    1 person found this answer helpful.

  2. Sedat SALMAN 13,180 Reputation points
    2023-05-25T05:09:23.7166667+00:00
    startingNumberOfVMs = 1;
    maxNumberOfVMs = 20; // maximum number of VMs you want
    samplePercentThreshold = 0.7;
    sampleDuration = TimeInterval_Minute * 3; 
    // Get the last sample
    $sample = $CPUPercent.GetSamplePercent(sampleDuration);
    // If the average CPU usage was more than 70%, increment the number of nodes
    $TargetDedicated = ($sample > samplePercentThreshold ? startingNumberOfVMs + 1 : startingNumberOfVMs);
    // Always keep the number of nodes between the starting number and the maximum
    $TargetDedicated = max(startingNumberOfVMs, min($TargetDedicated, maxNumberOfVMs));