[geode] branch support/1.15 updated: GEODE-10385: User Guide - Remove bad G1GC tuning advice (#7815)

[db...@apache.org]

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dbarnes pushed a commit to branch support/1.15
in repository https://gitbox.apache.org/repos/asf/geode.git


The following commit(s) were added to refs/heads/support/1.15 by this push:
     new 8cc780a557 GEODE-10385: User Guide - Remove bad G1GC tuning advice (#7815)
8cc780a557 is described below

commit 8cc780a557ad9052a27c12de00e18ac0bdf1016c
Author: Dave Barnes <db...@apache.org>
AuthorDate: Thu Jun 23 09:59:03 2022 -0700

    GEODE-10385: User Guide - Remove bad G1GC tuning advice (#7815)
---
 geode-docs/managing/heap_use/heap_management.html.md.erb | 1 -
 1 file changed, 1 deletion(-)

diff --git a/geode-docs/managing/heap_use/heap_management.html.md.erb b/geode-docs/managing/heap_use/heap_management.html.md.erb
index 682d7113e9..b138716574 100644
--- a/geode-docs/managing/heap_use/heap_management.html.md.erb
+++ b/geode-docs/managing/heap_use/heap_management.html.md.erb
@@ -153,7 +153,6 @@ $ gfsh start server --name=app.MyApplication --initial-heap=30m --max-heap=30m \
 Although the garbage first (G1) garbage collector works effectively with <%=vars.product_name_long%>, issues can arise in some cases due to the differences between CMS and G1.
 For example, G1 by design is not able to set a maximum tenured heap size, so when this value is requested from the garbage collector, it reports the total heap maximum size. This impacts <%=vars.product_name_long%>, as the resource manager uses the maximum size of the tenured heap size to calculate the value in bytes of the eviction and critical percentages.
 Extensive testing is recommended before using G1 garbage collector. See your JVM documentation for all JVM-specific settings that can be used to improve garbage collection (GC) response.
-If you find the <%=vars.product_name_long%> Resource Manager does not detect crossing the eviction or critical threshold quickly enough, it has been observed that its responsiveness is increased by reducing the default value of `--J-XX:MaxGCPauseMillis=VALUE` JVM parameter (which is `200`). Be sure to take into account that this change also increases the amount of time spent in garbage collection.
 
 Size of objects stored on a region must also be taken into account. If the primary heap objects you allocate are larger than 50 percent of the G1 region size (what are called "humongous" objects), this can cause the JVM to report `out of heap memory` when it has used only 50 percent of the heap.
 The default G1 region size is 1 Mb; it can be increased up to 32 Mb (with values that are always a power of 2) by using the `--J-XX:G1HeapRegionSize=VALUE` JVM parameter. If you are using large objects and want to use G1GC without increasing its heap region size (or if your values are larger than 16 Mb), then you could configure your <%=vars.product_name_long%> regions to store the large values off-heap. However, even if you do that the large off-heap values will allocate large temporary [...]