• Forums
    • Public Forums
      • Community Connect
      • Dynatrace
        • Dynatrace Open Q&A
      • Application Monitoring & UEM
        • AppMon & UEM Open Q&A
      • Network Application Monitoring
        • NAM Open Q&A
  • Home /
  • Public Forums /
  • Application Monitoring & UEM /
  • AppMon & UEM Open Q&A /
avatar image
Question by Ira W. · Jul 18, 2012 at 10:18 PM · web performance monitoring

Suspension question?

Hello
I am hoping someone can help me understand what we am seeing in dynaTrace.
In our production environment we am seeing some web Requests with really high Suspension percents (example we have a request that is 100 seconds and 78% is sitting in suspension.). As we look closer at where the suspensions are happening we notice it is anytime we are interacting with the database.
We are here asking this question because we found in documentation that suspension time is in correlation with the GC. Is this suspension hiding something else going on like waiting for SQL to respond?

Any help would be great

Comment

People who like this

0 Show 0
10 |2000000 characters needed characters left characters exceeded
  • Viewable by all users
  • Viewable by moderators
  • Viewable by moderators and the original poster
  • Advanced visibility
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 10 attachments (including images) can be used with a maximum of 50.0 MiB each and 250.0 MiB total.

2 Replies

  • Sort: 
  • Most voted
  • Newest
  • Oldest
avatar image

Answer by Connor G. · Jul 09, 2015 at 05:28 PM

Hey Andi,

There's currently testing going on with an application that seems to be exhibiting the same issues you mentioned here. We have a large amount of suspension time that occurs during socketread methods. 

 

Here's a before shot. 

And the same shot after we did some tuning to the memory and GC options

 

It's improved, but we still are seeing some pretty gnarly GC times in the young gen. We recently added more survivor space than is seen above, but didn't get any performance returns from the change.

There is a large amount of unused old gen space now which makes me consider lowering the tenuring threshold so we can begin using up that free space.

Any suggestions what else to do here?

Comment

People who like this

0 Show 1 · Share
10 |2000000 characters needed characters left characters exceeded
  • Viewable by all users
  • Viewable by moderators
  • Viewable by moderators and the original poster
  • Advanced visibility
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 10 attachments (including images) can be used with a maximum of 50.0 MiB each and 250.0 MiB total.

avatar image Andreas G. ♦ · Jul 10, 2015 at 06:05 AM 0
Share

I would take a look at the amount of data returned by your socketreads. You are probably retrieving a lot of data from your external system (Database, Web Services, ...) - and that consumes memory. tweaking memory heap space will obviously help a bit but it doesnt really address the issue in case you really retrieve TOO MUCH data. I would really analyze the data your app pulls in. Maybe this can be optimized. With that you reduce memory overhead and will bring down GC

avatar image

Answer by Andreas G. · Jul 19, 2012 at 10:15 AM

Waiting for SQL would normally show up as I/O. In your case I assume you see the Suspension time on your executeQuery call - correct?
If you constantly see this then it is an indication that the JDBC/ADO.NET implementation requires a lot of memory to e.g: fetch the results and keep them in memory - this could cause a GC and therefore you see it there. It could however also be that the GC just really kicks in at the time of the SQL - caused by some other component that requested memory.

We have an excellent chapter on our online performance book that explains memory management and how to analyze GC activity. you may want to check it out: https://book.dynatrace.com/content/memory/how-garbage-collection-works.aspx

Comment

People who like this

0 Show 0 · Share
10 |2000000 characters needed characters left characters exceeded
  • Viewable by all users
  • Viewable by moderators
  • Viewable by moderators and the original poster
  • Advanced visibility
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 10 attachments (including images) can be used with a maximum of 50.0 MiB each and 250.0 MiB total.

How to get started

First steps in the forum
Read Community User Guide
Best practices of using forum

NAM 2019 SP5 is available


Check the RHEL support added in the latest NAM service pack.

Learn more

LIVE WEBINAR

"Performance Clinic - Monitoring as a Self Service with Dynatrace"


JANUARY 15, 3:00 PM GMT / 10:00 AM ET

Register here

Follow this Question

Answers Answers and Comments

3 People are following this question.

avatar image avatar image avatar image

Related Questions

Business Transactions out out Mobile User Actions

Release of JavaScript supported by dtagent_xxxx js

Should I see these 409 errors in dT?

smarter action names for BSM

Split by Connection Type

Forum Tags

dotnet mobile monitoring load iis 6.5 kubernetes mainframe rest api dashboard framework 7.0 appmon 7 health monitoring adk log monitoring services auto-detection uem webserver test automation license web performance monitoring ios nam probe collector migration mq web services knowledge sharing reports window java hybris javascript appmon sensors good to know extensions search 6.3+ server documentation easytravel web dashboard kibana system profile purelytics docker splunk 6.1 process groups account 7.2 rest dynatrace saas spa guardian appmon administration production user actions postgresql upgrade oneagent measures security Dynatrace Managed transactionflow technologies diagnostics user session monitoring unique users continuous delivery sharing configuration alerting NGINX splitting business transaction client 6.3 installation database scheduler apache mobileapp RUM php dashlet azure purepath agent 7.1 appmonsaas messagebroker nodejs 6.2 android sensor performance warehouse
  • Forums
  • Public Forums
    • Community Connect
    • Dynatrace
      • Dynatrace Open Q&A
    • Application Monitoring & UEM
      • AppMon & UEM Open Q&A
    • Network Application Monitoring
      • NAM Open Q&A