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Re: [RFC] Vector (string?) growth factor of 1.5 (insted of 2)
- From: Paolo Carlini <pcarlini at suse dot de>
- To: Dhruv Matani <dhruvbird at gmx dot net>
- Cc: libstdc++ <libstdc++ at gcc dot gnu dot org>
- Date: Mon, 02 Feb 2004 17:46:16 +0100
- Subject: Re: [RFC] Vector (string?) growth factor of 1.5 (insted of 2)
- References: <401E6B2A.5020909@suse.de> <1075740024.1428.8.camel@home.free>
Dhruv Matani wrote:
Have you tried for vector<pod> and vector<with_non_trivial_copy_ctor>?
such as std::string? How much is the difference for bot approaches with
2 and 1.5 as the growth factor? Does the performance improve as the size
of the vector increases or does it deprove? What about memory
fragmentation using the specialized libstdc++-v3 allocators? Are there
any redundant copies made with using the specialized allocators?
For now, I'm just reading attentitevely the whole discussion (to which
you participated, I think!)
Linux glibc calls mmap for large requests.
This is a suggestion that I find particularly interesting. Was also put
forward in the thread by James Kanze. Consider that we plan to have some
infrastructure for mmap anyway, since we want to use it when possible in
iostreams.
Do you think that this can be worked out with Gabriel Dos Reis in
conjunction with the plan for allowing reallocation of memory for
vectors?
Dunno...
Paolo.