Huge pages on PPC64

[Gustavo Romero]

Hi,

Is Huge Pages properly supported by OpenJDK on PPC64 and PPC64 LE?

I did a simple test like:

# uname -a
Linux tm 4.4.0-38-generic #57-Ubuntu SMP Tue Sep 6 15:42:33 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux
# fgrep Huge /proc/meminfo
AnonHugePages:     12288 kB
HugePages_Total:     256
HugePages_Free:      256
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
# java -XX:+PrintCommandLineFlags -XX:+UseLargePages -Xms256m -Xmx256m StrictMath_cos
-XX:InitialHeapSize=268435456 -XX:MaxHeapSize=268435456 -XX:+PrintCommandLineFlags -XX:+UseCompressedClassPointers -XX:+UseCompressedOops -XX:+UseLargePages -XX:+UseParallelGC
0.1709843554185943
# java -version
openjdk version "1.8.0_91"
OpenJDK Runtime Environment (build 1.8.0_91-8u91-b14-3ubuntu1~16.04.1-b14)
OpenJDK 64-Bit Server VM (build 25.91-b14, mixed mode)


on x64 all went well, but on PPC64 I'm getting an error as if the amount
of space requested was greater than HugePages_Total * Hugepagesize, which
is no true:

# uname -a
Linux pub 4.5.0-rc4-powerpc64le #1 SMP Debian 4.5~rc4-1~exp1 (2016-02-18) ppc64le GNU/Linux
# fgrep Huge /proc/meminfo
AnonHugePages:   7831552 kB
HugePages_Total:    1024
HugePages_Free:     1024
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:      16384 kB
# java -XX:+PrintCommandLineFlags -Xms256m -Xmx256m -XX:+UseLargePages StrictMath_cos
-XX:InitialHeapSize=268435456 -XX:MaxHeapSize=268435456 -XX:+PrintCommandLineFlags -XX:+UseCompressedClassPointers -XX:+UseCompressedOops -XX:+UseLargePages -XX:+UseParallelGC
OpenJDK 64-Bit Server VM warning: Failed to reserve large pages memory req_addr: 0x00000000f0000000 bytes: 268435456 (errno = 16).
OpenJDK 64-Bit Server VM warning: Failed to reserve large pages memory req_addr: 0x00000007b0000000 bytes: 268435456 (errno = 16).
OpenJDK 64-Bit Server VM warning: Failed to reserve large pages memory req_addr: 0x0000000000000000 bytes: 301989888 (errno = 16).
# java -version
openjdk version "1.8.0_102"
OpenJDK Runtime Environment (build 1.8.0_102-8u102-b14.1-2-b14)
OpenJDK 64-Bit Server VM (build 25.102-b14, mixed mode)


Am I missing something here or something is planned (tho I could not find a JEP or JBS on it...)?

Thank you.


Regards,
Gustavo