why tcmalloc 2.0 use much more memory than 1.7 on x86_64

[GoogleCodeExporter]

What steps will reproduce the problem?
1.build libunwind 1.1 and gperftools 2.0 with default option
2.link my program with -ltcmalloc
3.run my program and about 4G virtual memory is used
4.using tcmalloc 1.7 instead, no any other environment changed
5.run my program with the same load and pressure,only 1.7G virturl memory is 
used
6.besides,on 32bit platform,my program linked with tcmalloc 1.7 use nearly 1.7G 
memory under the same load,so I am confused why tcmalloc 2.0 use so much memory.

Is there anything special I have to do when using tcmalloc 2.0?

Anyone also has met such situation ?

What is the expected output? What do you see instead?

What version of the product are you using? On what operating system?
libunwind 1.1
tcmalloc 2.0/1.7
SUSE 10 x86_64

Please provide any additional information below.

Thank you very much!

Original issue reported on code.google.com by dp.chan...@gmail.com on 22 May 2013 at 2:30

[GoogleCodeExporter]

Are you seeing just an increase of virtual memory or in RSS as well? Are you 
seeing any performance difference?

I can't recall if internal thread storage changed over releases, but usually an 
increase on virtual memory is not an issue if RSS remains in control.

Original comment by zatr...@gmail.com on 28 May 2013 at 1:58

[GoogleCodeExporter]

Please, consider testing with latest svn trunk. Or posting test program.

Original comment by alkondratenko on 6 Jul 2013 at 11:17