From 8a9bd672af892be57347b678bccb481f026bc132 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Sun, 2 Feb 2014 19:19:04 -0200 Subject: [PATCH] Update README with PowerPC specifics notes --- README | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/README b/README index bffc617..3d7de6b 100644 --- a/README +++ b/README @@ -1,3 +1,23 @@ +POWERPC NOTES +------------- + +This branch contains PowerPC specific performance tunings and +platform fixes. All test, including heap and cpu profiler, works +on powerpc32, powerpc64, and powerpc64le. + +On newer distros with 64k page size, it is highly recommended +to configure with '-DTCMALLOC_LARGE_PAGES64K' CXX flag. It turns the +internal page allocation to use 64K page size and avoid more syscalls +to allocate memory from OS. + +The default value of objects transfered between central list and +thread cache is increased from 32 to 32768. This is a performance +improvement, specially on programs that allocate lot of objects of +the same size (like a std::map with a large set of elements). +The value can be change by setting the environment variable +TCMALLOC_TRANSFER_NUM_OBJ. + + IMPORTANT NOTE FOR 64-BIT USERS ------------------------------- There are known issues with some perftools functionality on x86_64