Re: [Iverilog-devel] Too much memory usage when compling big netlist

[Stephen W. <st...@ic...>]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Bruce Cheng wrote:
> Hi Cary,
> 
>    I see.
> 
>    Besides, I have long noticed that you use your own perm_string
>    class instead of C++ String class to manage strings. Is it because
>    C++ String consumes lots of memory?
> 
> 
> Bruce

The reason for that is to save memory. In particular, it saves
allocation overhead. When you are creating tons of short strings
that you never intend to release, then much memory can be saved
by allocating big chunks of memory and farming bytes out to strings
tightly packed into that memory. No deallocation is allowed, so
no allocation overhead is needed.

This made a big difference in memory use when first implemented.

- --
Steve Williams                "The woods are lovely, dark and deep.
steve at icarus.com           But I have promises to keep,
http://www.icarus.com         and lines to code before I sleep,
http://www.picturel.com       And lines to code before I sleep."
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.4-svn0 (GNU/Linux)
Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org

iD8DBQFLD/i/rPt1Sc2b3ikRAgnLAJ9citnoVUBQQuiIYfwcOakQzh1klQCg2KV1
nAGd1mg83sk9nRKSigovz9Y=
=KQ5g
-----END PGP SIGNATURE-----