topic How to calculate maximum *nix heavy forwarder capacity/thruput based on memory & cores in Getting Data In

How to calculate maximum *nix heavy forwarder capacity/thruput based on memory & cores

abrarfakhri — Wed, 03 Feb 2016 20:40:50 GMT

Fellow Splunkers!
I've spent a lot of time on both the answers and splunkbase sites but can't seem to find a simple formula for this.

I am trying to determine the maximum *nix heavy forwarder capacity with 2 cores and 4GB physical memory. I know this is not up to standard but I am guessing there must be a simple formula we can apply to determine thruput.

Re: How to calculate maximum *nix heavy forwarder capacity/thruput based on memory & cores

abrarfakhri — Wed, 03 Feb 2016 20:47:40 GMT

To be more specific, the maximum thruput should be measured in max events per sec, max kbps, max load etc.

Here is the current readout from metrics.log:

02-03-2016 15:11:51.891 -0500 INFO  Metrics - group=thruput, name=index_thruput, instantaneous_kbps=762.769461, instantaneous_eps=1963.774257, average_kbps=862.     173209, total_k_processed=4834560107.000000, kb=23645.852539, ev=60877.000000, load_average=2.830000

Re: How to calculate maximum *nix heavy forwarder capacity/thruput based on memory & cores

somesoni2 — Wed, 03 Feb 2016 22:50:07 GMT

This should give you helpful stats

Query1 - overall stats per host

index=_internal sourcetype=splunkd source=*metrics.log group=per_host_thruput | stats max(kbps) as max_kbps max(eps) as max_eps max(kb) as max_kb max(ev) as max_events by host

Query2 - for different granularity

index=_internal sourcetype=splunkd source=*metrics.log group=per_host_thruput | bucket span=1m _time | stats max(kbps) as max_kbps max(eps) as max_eps sum(kb) as kb sum(ev) as ev by _time,host | bucket span=1h _time | stats max(max_kbps) as max_kbps max(max_eps) as max_eps max(kb) as max_kbpm max(ev) as max_epm sum(kb) as kb sum(ev) as ev by _time, host | bucket span=1d _time | stats max(max_kbps) as max_kbps max(max_eps) as max_eps  max(max_kbpm) as max_kbpm max(max_epm) as max_epm max(kb) as max_kbph max(ev) as max_eph sum(kb) as kb sum(ev) as ev by _time, host

Re: How to calculate maximum *nix heavy forwarder capacity/thruput based on memory & cores

abrarfakhri — Wed, 03 Feb 2016 23:30:44 GMT

somesoni2, I appreciate your response. But, this is not what I was looking for. If I am reading this right, I think what the above queries provide is the maximum thruput that the HF is achieving today. What I am looking for is the maxmimum thruput the HF can achieve given the limitation of 2 cores and 4GB memory.

This would be similar to asking "How many concurrent searches can a SH achieve?" Well, the answer is dependent on the # of cores.

Hope that clarifies the question a bit more.
Looking forward to your response!

Re: How to calculate maximum *nix heavy forwarder capacity/thruput based on memory & cores

abrarfakhri — Mon, 08 Feb 2016 22:23:50 GMT

I still hope someone would be able to answer this question...

Re: How to calculate maximum *nix heavy forwarder capacity/thruput based on memory & cores

masonmorales — Tue, 09 Feb 2016 00:31:58 GMT

There isn't a formula for what you are asking. Just like there isn't a formula for determining how many search heads you should have. There are simply too many variables at play.

Your best bet would be to setup a test instance with your given specs, load the apps you plan on running, and then send a bunch of test data at it until you see either full queues in splunkd.log or you've exhausted CPU and/or memory resources.