KB-2109 G1 garbage collector FAQ

Parmida Borhani — Thu, 16 Sep 2021 11:11:16 GMT

Current Revision posted to Appian Knowledge Base by Parmida Borhani on 9/16/2021 11:11:16 AM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?
On a site configured with high availability (HA), why do the servers have different heap utilization profiles?

Why is my heap profile different after upgrading to 20.1?

Appian uses the G1 Java garbage collector beginning in Appian 20.1. Thresholds dictating garbage collection frequency and volume have changed. This is due to the change in garbage collection strategy in order to optimize for both system stability and performance. Therefore, Appian Cloud sites may display new heap utilization patterns despite unchanged usage.

What should I expect when looking at Cloud Insights?

Heap usage may continue to fluctuate even during periods of no system activity due to Appian system components running in the background. It is common to see fluctuations as high as 80%. Below is an example of a common heap utilization pattern while using the G1 garbage collector:

On a site configured with high availability (HA), why do the servers have different heap utilization profiles?

Each server in a HA configuration manages heap independently, so it is not uncommon for servers to differ in their usage profiles. This is especially common on startup, and is not indicative of an issue.

Affected Versions

This article applies to Appian 20.1 and later, as well as all versions of Appian using the G1 garbage collector.

Last Reviewed: September 2021

Tags: heap, application server, infrastructure, FAQ

KB-2109 G1 garbage collector FAQ

Parmida Borhani — Fri, 24 Apr 2020 02:03:07 GMT

Revision 12 posted to Appian Knowledge Base by Parmida Borhani on 4/24/2020 2:03:07 AM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?

Why is my heap profile different after upgrading to 20.1?

What should I expect when looking at Cloud Insights?

Affected Versions

This article applies to Appian 20.1 and later, as well as all versions of Appian using the G1 garbage collector.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

KB-2109 G1 garbage collector FAQ

Parmida Borhani — Fri, 24 Apr 2020 02:03:07 GMT

Revision 13 posted to Appian Knowledge Base by Parmida Borhani on 4/24/2020 2:03:07 AM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?

Why is my heap profile different after upgrading to 20.1?

What should I expect when looking at Cloud Insights?

Affected Versions

This article applies to Appian 20.1 and later, as well as all versions of Appian using the G1 garbage collector.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

KB-2109 G1 garbage collector FAQ

Parmida Borhani — Fri, 24 Apr 2020 02:02:37 GMT

Revision 11 posted to Appian Knowledge Base by Parmida Borhani on 4/24/2020 2:02:37 AM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?

Why is my heap profile different after upgrading to 20.1?

What should I expect when looking at Cloud Insights?

Affected Versions

This article applies to Appian 20.1 and later, as well as all versions of Appian using the G1 garbage collector.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

Tom Ryan — Thu, 23 Apr 2020 22:35:47 GMT

Revision 10 posted to Appian Knowledge Base by Tom Ryan on 4/23/2020 10:35:47 PM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?

Why is my heap profile different after upgrading to 20.1?

Appian now uses the G1 Java garbage collector. Thresholds dictating garbage collection frequency and volume have changed. This is due to the change in garbage collection strategy in order to optimize for both system stability and performance. Therefore, Appian Cloud sites may display new heap utilization patterns despite unchanged usage.

What should I expect when looking at Cloud Insights?

Affected Versions

This article applies to Appian 20.1 and later, as well as all versions of Appian using the G1 garbage collector.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

James Lee — Thu, 23 Apr 2020 21:54:51 GMT

Revision 9 posted to Appian Knowledge Base by James Lee on 4/23/2020 9:54:51 PM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?
Why change garbage collectors?

Why is my heap profile different after upgrading to 20.1?

What should I expect when looking at Cloud Insights?

Why change garbage collectors?

G1 is the default garbage collector for JDK 9 and above. This garbage collector performs better on large heaps and leads to shorter system pauses during garbage collection.

Affected Versions

This article applies to Appian 20.1 and later, as well as all versions of Appian using the G1 garbage collector.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

James Lee — Thu, 02 Apr 2020 21:17:51 GMT

Revision 8 posted to Appian Knowledge Base by James Lee on 4/2/2020 9:17:51 PM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?
Why change garbage collectors?

Why is my heap profile different after upgrading to 20.1?

Appian now uses the G1 Java garbage collector. Thresholds dictating garbage collection frequency and volume have changed. Therefore, Appian Cloud sites may display new heap utilization patterns despite unchanged usage.

What should I expect when looking at Cloud Insights?

Heap usage may fluctuate frequently, even on sites that are not under load. Below is an example of expected, healthy heap utilization with G1 on Cloud Insights.

Why change garbage collectors?

G1 is the default garbage collector for JDK 9 and above. This garbage collector performs better on large heaps and leads to shorter system pauses during garbage collection.

Affected Versions

This article applies to Appian 20.1 and later, as well as all versions of Appian using the G1 garbage collector.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

Daniel DeVeau — Thu, 02 Apr 2020 14:38:02 GMT

Revision 7 posted to Appian Knowledge Base by Daniel DeVeau on 4/2/2020 2:38:02 PM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?
Why change garbage collectors?

Why is my heap profile different after upgrading to 20.1?

Appian now uses the G1 Java garbage collector. Thresholds for when garbage collection occurs and what data is collected have changed, therefore Appian Cloud sites may display new heap utilization patterns despite unchanged usage.

What should I expect when looking at Cloud Insights?

Heap usage may fluctuate frequently, even on sites that are not under load. Below is an example of expected, healthy heap utilization with G1 on Cloud Insights.

Why change garbage collectors?

G1 is the default garbage collector for JDK 9 and above. This garbage collector performs better on large heaps and leads to shorter system pauses during garbage collection.

Affected Versions

This article applies to Appian 20.1 and later.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

Daniel DeVeau — Thu, 02 Apr 2020 14:37:19 GMT

Revision 6 posted to Appian Knowledge Base by Daniel DeVeau on 4/2/2020 2:37:19 PM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?
Why change garbage collectors?

Why is my heap profile different after upgrading to 20.1?

What should I expect when looking at Cloud Insights?

Heap usage may fluctuate frequently, even on sites that are not under load. Below is an example of expected, healthy heap utilization on Cloud Insights.

Why change garbage collectors?

G1 is the default garbage collector for JDK 9 and above. This garbage collector performs better on large heaps and leads to shorter system pauses during garbage collection.

Affected Versions

This article applies to Appian 20.1 and later.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

Daniel DeVeau — Thu, 02 Apr 2020 14:35:41 GMT

Revision 5 posted to Appian Knowledge Base by Daniel DeVeau on 4/2/2020 2:35:41 PM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?
Why change garbage collectors?

Why is my heap profile different after upgrading to 20.1?

What should I expect when looking at Cloud Insights?

Heap usage may fluctuate frequently, even on sites that are not under load. Below is an example of expected, healthy heap utilization on Cloud Insights

Why change?

G1 is the default garbage collector for JDK 9 and above. This garbage collector performs better on large heaps and leads to shorter system pauses during garbage collection.

Affected Versions

This article applies to Appian 20.1 and later.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

Daniel DeVeau — Thu, 02 Apr 2020 13:45:15 GMT

Revision 4 posted to Appian Knowledge Base by Daniel DeVeau on 4/2/2020 1:45:15 PM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?Appian now uses the G1 Java garbage collector

Why is my heap profile different after upgrading to 20.1?

Format each question as shown here. The question should be bold with the corresponding answer below.

Examples:

Affected Versions

This article applies to Appian 20.1 and later.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

Daniel DeVeau — Thu, 02 Apr 2020 13:44:49 GMT

Revision 3 posted to Appian Knowledge Base by Daniel DeVeau on 4/2/2020 1:44:49 PM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?Appian now uses the G1 Java garbage collector

Why is my heap profile different after upgrading to 20.1?

Format each question as shown here. The question should be bold with the corresponding answer below.

Examples:

Affected Versions

This article applies to Appian 20.1 and later.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

Daniel DeVeau — Thu, 02 Apr 2020 13:42:41 GMT

Revision 2 posted to Appian Knowledge Base by Daniel DeVeau on 4/2/2020 1:42:41 PM

Table of Contents:

Why is my heap profile different after upgrading to 20.1?
What should I expect when looking at Cloud Insights?Appian now uses the G1 Java garbage collector

Why is my heap profile different after upgrading to 20.1?

Format each question as shown here. The question should be bold with the corresponding answer below.

Examples:

Affected Versions

This article applies to Appian 20.1 and later.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ

DRAFT SP-4177 G1 Garbage Collector FAQ

Daniel DeVeau — Wed, 01 Apr 2020 20:43:41 GMT

Revision 1 posted to Appian Knowledge Base by Daniel DeVeau on 4/1/2020 8:43:41 PM

Table of Contents:

How should the Q and A be formatted?

How should the Q and A be formatted?

Format each question as shown here. The question should be bold with the corresponding answer below.

Examples:

Affected Versions

This article applies to Appian 20.1 and later.

Last Reviewed: April 2020

Tags: heap, application server, infrastructure, FAQ