Make reserved_size for compressed class space and metaspace respect the ergo-initialized CompressedClassSpaceSize flag value (original) (raw)

Man Cao manc at google.com
Sat Dec 9 02:57:12 UTC 2017

Hi Yasumasa,

Thanks for the review! Although I think moving or not moving "CompressedClassSpaceSize = align_size_down_bounded()" are equivalent because of logic of alignment and FLAG_SET_ERGO, I made the change you suggested anyway. The new patch is attached and inlined below.

--- old/src/hotspot/share/memory/metaspace.cpp 2017-12-08 18:42:48.960285998 -0800 +++ new/src/hotspot/share/memory/metaspace.cpp 2017-12-08 18:42:48.600288972 -0800 @@ -3322,7 +3322,6 @@ MaxMetaspaceExpansion = align_down_bounded(MaxMetaspaceExpansion, _commit_alignment);

CompressedClassSpaceSize = align_down_bounded(CompressedClassSpaceSize, _reserve_alignment);

@@ -3341,6 +3340,7 @@ min_metaspace_sz); }

void Metaspace::global_initialize() {

Thanks, Man

On Thu, Dec 7, 2017 at 9:44 PM, Yasumasa Suenaga <yasuenag at gmail.com> wrote:

Hi Man,

CompressedClassSpaceSize might be modified by FLAGSETERGO. So I think you need to move setcompressedclassspacesize() only.

Thanks, Yasumasa

2017-12-08 3:42 GMT+09:00 Man Cao <manc at google.com>: > Hello, > > This is a friendly ping. Could anyone review or sponsor this change? It's > just a two-liner change. > > -Man > > On Thu, Nov 30, 2017 at 2:03 PM, Man Cao <manc at google.com> wrote: >> >> I realized that the email attachment is probably dropped by the mailing >> list, so below is the inlined patch. >> >> --- old/src/hotspot/share/memory/metaspace.cpp 2017-11-29 >> 14:56:59.017118444 -0800 >> +++ new/src/hotspot/share/memory/metaspace.cpp 2017-11-29 >> 14:56:58.657121375 -0800 >> @@ -3321,9 +3321,6 @@ >> MinMetaspaceExpansion = aligndownbounded(MinMetaspaceExpansion, >> commitalignment); >> MaxMetaspaceExpansion = aligndownbounded(MaxMetaspaceExpansion, >> commitalignment); >> >> - CompressedClassSpaceSize = aligndownbounded( CompressedClassSpaceSize, >> reservealignment); >> - setcompressedclassspacesize(CompressedClassSpaceSize); >> - >> // Initial virtual space size will be calculated at globalinitialize() >> sizet minmetaspacesz = >> VIRTUALSPACEMULTIPLIER * InitialBootClassLoaderMetaspaceSize; >> @@ -3341,6 +3338,8 @@ >> minmetaspacesz); >> } >> >> + CompressedClassSpaceSize = aligndownbounded( CompressedClassSpaceSize, >> reservealignment); >> + setcompressedclassspacesize(CompressedClassSpaceSize); >> } >> >> void Metaspace::globalinitialize() { >> >> Best, >> Man >> >> On Wed, Nov 29, 2017 at 3:21 PM, Man Cao <manc at google.com> wrote: >>> >>> Hello, >>> >>> This patch is a follow-up fix for >>> https://bugs.openjdk.java.net/browse/JDK-8087291 >>> >>> This patch moves the call to setcompressedclassspacesize() after the >>> flag value for CompressedClassSpaceSize is ergo-initialized, fixing the >>> issue that the reserved size for compressed class space and metaspace is >>> excessively large when MaxMetaspaceSize is set to a small value. More >>> discussion about it is available here: >>> >>> http://mail.openjdk.java.net/pipermail/hotspot-runtime-dev/ 2017-November/025200.html >>> >>> This code patch is attached. Could anyone review and/or sponsor this >>> patch? >>> >>> Best, >>> Man >> >> > -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.openjdk.org/pipermail/hotspot-gc-dev/attachments/20171208/937e16fc/attachment.htm> -------------- next part -------------- A non-text attachment was scrubbed... Name: jdk10hs.patch Type: text/x-patch Size: 716 bytes Desc: not available URL: <https://mail.openjdk.org/pipermail/hotspot-gc-dev/attachments/20171208/937e16fc/jdk10hs.patch>

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