Re: [PATCH v5 02/15] read-cache: allow to keep mmap'd memory after reading

On Wed, 2016-04-20 at 16:26 +0700, Duy Nguyen wrote:

On Wed, Apr 20, 2016 at 6:27 AM, David Turner <
dturner@twopensource.com> wrote:

quoted

From: Nguyễn Thái Ngọc Duy <redacted>

Later, we will introduce git index-helper to share this memory with
other git processes.

Since the memory will be shared, it will never be unmapped
(although
the kernel may of course choose to page it out).

This is not entirely true. We do need to keep the mmap'd memory for
longer, even after read_index_from() finishes. But we do not share
the
exact same address space to other processes (memcpy is used in
index-helper.c:share_index()). We could even discard_index() at the
end of share_index(), but I think we keep it anyway just in case
another process asks, or when index is not updated.

Will reword.