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8228494: Update nroff version of man pages

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Reviewed-by: mchung
This commit is contained in:
Jonathan Gibbons 2019-07-23 11:30:31 -07:00
parent 6e90474edf
commit 5fc206ea7d
4 changed files with 639 additions and 10 deletions
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143
src/java.base/share/man/java.1
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@ -1868,17 +1868,21 @@ By default, this option is enabled.
.TP
.B \f[CB]\-XX:\-UseCompressedOops\f[R]
Disables the use of compressed pointers.
By default, this option is enabled, and compressed pointers are used
when Java heap sizes are less than 32 GB.
When this option is enabled, object references are represented as
32\-bit offsets instead of 64\-bit pointers, which typically increases
performance when running the application with Java heap sizes of less
than 32 GB.
This option works only for 64\-bit JVMs.
By default, this option is enabled, and compressed pointers are used.
This will automatically limit the maximum ergonomically determined Java
heap size to the maximum amount of memory that can be covered by
compressed pointers.
By default this range is 32 GB.
.RS
.PP
It\[aq]s also possible to use compressed pointers when Java heap sizes
are greater than 32 GB.
With compressed oops enabled, object references are represented as
32\-bit offsets instead of 64\-bit pointers, which typically increases
performance when running the application with Java heap sizes smaller
than the compressed oops pointer range.
This option works only for 64\-bit JVMs.
.PP
It\[aq]s possible to use compressed pointers with Java heap sizes
greater than 32 GB.
See the \f[CB]\-XX:ObjectAlignmentInBytes\f[R] option.
.RE
.TP
@ -3213,6 +3217,22 @@ The size of the heap for the young generation can be set using the
\f[CB]\-XX:NewSize\f[R] option.
.RE
.TP
.B \f[CB]\-XX:InitialRAMPercentage=\f[R]\f[I]percent\f[R]
Sets the initial amount of memory that the JVM will use for the Java
heap before applying ergonomics heuristics as a percentage of the
maximum amount determined as described in the \f[CB]\-XX:MaxRAM\f[R]
option.
The default value is 1.5625 percent.
.RS
.PP
The following example shows how to set the percentage of the initial
amount of memory used for the Java heap:
.RS
.PP
\f[CB]\-XX:InitialRAMPercentage=5\f[R]
.RE
.RE
.TP
.B \f[CB]\-XX:InitialSurvivorRatio=\f[R]\f[I]ratio\f[R]
Sets the initial survivor space ratio used by the throughput garbage
collector (which is enabled by the \f[CB]\-XX:+UseParallelGC\f[R] and/or
@ -3371,6 +3391,72 @@ The default value is set ergonomically.
.RS
.RE
.TP
.B \f[CB]\-XX:MaxRAM=\f[R]\f[I]size\f[R]
Sets the maximum amount of memory that the JVM may use for the Java heap
before applying ergonomics heuristics.
The default value is the maximum amount of available memory to the JVM
process or 128 GB, whichever is lower.
.RS
.PP
The maximum amount of available memory to the JVM process is the minimum
of the machine\[aq]s physical memory and any constraints set by the
environment (e.g.
container).
.PP
Specifying this option disables automatic use of compressed oops if the
combined result of this and other options influencing the maximum amount
of memory is larger than the range of memory addressable by compressed
oops.
See \f[CB]\-XX:UseCompressedOops\f[R] for further information about
compressed oops.
.PP
The following example shows how to set the maximum amount of available
memory for sizing the Java heap to 2 GB:
.RS
.PP
\f[CB]\-XX:MaxRAM=2G\f[R]
.RE
.RE
.TP
.B \f[CB]\-XX:MaxRAMPercentage=\f[R]\f[I]percent\f[R]
Sets the maximum amount of memory that the JVM may use for the Java heap
before applying ergonomics heuristics as a percentage of the maximum
amount determined as described in the \f[CB]\-XX:MaxRAM\f[R] option.
The default value is 25 percent.
.RS
.PP
Specifying this option disables automatic use of compressed oops if the
combined result of this and other options influencing the maximum amount
of memory is larger than the range of memory addressable by compressed
oops.
See \f[CB]\-XX:UseCompressedOops\f[R] for further information about
compressed oops.
.PP
The following example shows how to set the percentage of the maximum
amount of memory used for the Java heap:
.RS
.PP
\f[CB]\-XX:MaxRAMPercentage=75\f[R]
.RE
.RE
.TP
.B \f[CB]\-XX:MinRAMPercentage=\f[R]\f[I]percent\f[R]
Sets the maximum amount of memory that the JVM may use for the Java heap
before applying ergonomics heuristics as a percentage of the maximum
amount determined as described in the \f[CB]\-XX:MaxRAM\f[R] option for
small heaps.
A small heap is a heap of approximately 125 MB.
The default value is 50 percent.
.RS
.PP
The following example shows how to set the percentage of the maximum
amount of memory used for the Java heap for small heaps:
.RS
.PP
\f[CB]\-XX:MinRAMPercentage=75\f[R]
.RE
.RE
.TP
.B \f[CB]\-XX:MaxTenuringThreshold=\f[R]\f[I]threshold\f[R]
Sets the maximum tenuring threshold for use in adaptive GC sizing.
The largest value is 15.
@ -3802,6 +3888,45 @@ Since JDK 8u40 this option has not been required to use JFR.
.RS
.RE
.TP
.B \f[CB]\-XX:InitialRAMFraction=\f[R]\f[I]ratio\f[R]
Sets the initial amount of memory that the JVM may use for the Java heap
before applying ergonomics heuristics as a ratio of the maximum amount
determined as described in the \f[CB]\-XX:MaxRAM\f[R] option.
The default value is 64.
.RS
.PP
Use the option \f[CB]\-XX:InitialRAMPercentage\f[R] instead.
.RE
.TP
.B \f[CB]\-XX:MaxRAMFraction=\f[R]\f[I]ratio\f[R]
Sets the maximum amount of memory that the JVM may use for the Java heap
before applying ergonomics heuristics as a fraction of the maximum
amount determined as described in the \f[CB]\-XX:MaxRAM\f[R] option.
The default value is 4.
.RS
.PP
Specifying this option disables automatic use of compressed oops if the
combined result of this and other options influencing the maximum amount
of memory is larger than the range of memory addressable by compressed
oops.
See \f[CB]\-XX:UseCompressedOops\f[R] for further information about
compressed oops.
.PP
Use the option \f[CB]\-XX:MaxRAMPercentage\f[R] instead.
.RE
.TP
.B \f[CB]\-XX:MinRAMFraction=\f[R]\f[I]ratio\f[R]
Sets the maximum amount of memory that the JVM may use for the Java heap
before applying ergonomics heuristics as a fraction of the maximum
amount determined as described in the \f[CB]\-XX:MaxRAM\f[R] option for
small heaps.
A small heap is a heap of approximately 125 MB.
The default value is 2.
.RS
.PP
Use the option \f[CB]\-XX:MinRAMPercentage\f[R] instead.
.RE
.TP
.B \f[CB]\-XX:+TraceClassLoading\f[R]
Enables tracing of classes as they are loaded.
By default, this option is disabled and classes aren\[aq]t traced.