[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
gprof extreemly slow on reading a 64bit executable
From: |
Dirk-Jan Jongeneel |
Subject: |
gprof extreemly slow on reading a 64bit executable |
Date: |
Thu, 09 Feb 2006 10:13:07 +0100 |
User-agent: |
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7) Gecko/20040616 |
I have a large program compiled on rh72 as well as rhel3 using gcc3.2.3
or gcc4.0.2 (I use -fno-omit-frame-pointer in 64bit case else it would
not work at all there - but that seems to be a known issue) I use
binutils-2.13.2.1.
If I run gprof <executable> for the 32 bit it returns in 30 seconds with
no gmon.out. If I do that for the 64bit version it takes 25 min!!
I have also tried with binutils-2.16.1. and ran profile and gdb.
I see the following difference between the 32bit read and 64bit read.
_bfd_elf_find_nearest_line in elf.c calls
_bfd_dwarf2_find_nearest_line
in case of 32bit it returns with true but in case of 64bit it fails and
eventually calls
elf_find_function at the end.
It calls this thousands of times and spends 95% of cputime in there.
So the cause of slownes seems a problem in _bfd_dwarf2_find_nearest_line
not being able to find what it needs.
What can I do to debug/fix this issue?
Dirk-Jan
--
"CONFIDENTIALITY NOTICE: This e-mail may contain information that is
confidential and proprietary to Magma, and Magma hereby designates the
information in this e-mail as confidential. The information is
intended only for the use of the individual or entity named above. If
you are not the intended recipient, you are hereby notified that any
disclosure, copying, distribution or use of any of the information
contained in this transmission is strictly prohibited and that you
should immediately destroy this e-mail and its contents and notify
Magma."
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- gprof extreemly slow on reading a 64bit executable,
Dirk-Jan Jongeneel <=