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# IRC, freenode, #hurd, 2012-07-30
<mcsim> Why for big buffers in ext2fs used own allocator, that just
allocates many pages at once, instead of using malloc?
<mcsim> i.e. can I replace it with malloc, because it just complicates
things?
<braunr> mcsim: probably because of alignment
<braunr> what gets complicated by that ?
<mcsim> braunr: than valloc?
<mcsim> braunr: this allocator allows to allocate only buffer with size of
vm_page_size.
<mcsim> valloc just would be clearer.
<braunr> valloc ?
<braunr> valloc is obsolete
<mcsim> braunr: than memalign or posix_memalign?
<mcsim> memalign obsolete too... would posix_memalign be eligible?
<braunr> mcsim: why memalign instead of the custom allocator ?
<mcsim> because, I think, it is clearer. Also, since I need to allocate any
amount of pages, not just one, I have to edit custom allocator. Although
it is not hard, but using ready stuff seems more sane for me.
<mcsim> braunr: ^
<braunr> right, but make sure posix_memalign doesn't create too much
overhead
<mcsim> braunr: what kind of overhead?
<braunr> fragmentation
<braunr> i assume the glibc implementation is careful about that, but still
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