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Author	SHA1	Message	Date
Linus Torvalds	3e4339e6f9	Remove "refs" field from "struct object" This shrinks "struct object" to the absolutely minimal size possible. It now contains /only/ the object flags and the SHA1 hash name of the object. The "refs" field, which is really needed only for fsck, is maintained in a separate hashed lookup-table, allowing all normal users to totally ignore it. This helps memory usage, although not as much as I hoped: it looks like the allocation overhead of malloc (and the alignment constraints in particular) means that while the structure size shrinks, the actual allocation overhead mostly does not. [ That said: memory usage is actually down, but not as much as it should be: I suspect just one of the object types actually ended up shrinking its effective allocation size. To get to the next level, we probably need specialized allocators that don't pad the allocation more than necessary. ] The separation makes for some code cleanup, though, and makes the ref tracking that fsck wants a clearly separate thing. Signed-off-by: Linus Torvalds <torvalds@osdl.org> Signed-off-by: Junio C Hamano <junkio@cox.net>	19 years ago

Author

SHA1

Message

Date

Linus Torvalds

3e4339e6f9

Remove "refs" field from "struct object"

This shrinks "struct object" to the absolutely minimal size possible.
It now contains /only/ the object flags and the SHA1 hash name of the
object.

The "refs" field, which is really needed only for fsck, is maintained in
a separate hashed lookup-table, allowing all normal users to totally
ignore it.

This helps memory usage, although not as much as I hoped: it looks like
the allocation overhead of malloc (and the alignment constraints in
particular) means that while the structure size shrinks, the actual
allocation overhead mostly does not.

[ That said: memory usage is actually down, but not as much as it should
  be: I suspect just one of the object types actually ended up shrinking
  its effective allocation size.

  To get to the next level, we probably need specialized allocators that
  don't pad the allocation more than necessary. ]

The separation makes for some code cleanup, though, and makes the ref
tracking that fsck wants a clearly separate thing.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>

19 years ago

1 Commits (fefe81c9964a12394d6ea81ce474ff402f0eb070)