Implement `calloc{,Bytes,Array,Array0}` allocators
Hi everyone, There is a proposal [1] (with implemented revision) to implement zero-initialising versions of malloc{,Bytes,Array,Array0} - Add calloc and callocBytes to Foreign.Marshal.Alloc. - Add callocArray and callocArray0 to Foreign.Marshal.Array. The benefit is that you can allocate required amount of memory and be certain that it will be cleared (set with zeroes) before you use it. Original discussion took a place in `fillBytes` [1] and was publicised on that mailing list [2]. Please share your thoughts. Thank you. [1] https://phabricator.haskell.org/D527 [2] https://phabricator.haskell.org/D461#11541 [3] https://www.haskell.org/pipermail/libraries/2014-November/024251.html -- alex p
+1, 'nuff said. I was very surprised they weren't already there, and calloc can be 2x faster than any malloc/set to 0 nonsense. -Edward On Sat, Nov 29, 2014 at 11:05 AM, Oleksandr Petrov < oleksandr.petrov@gmail.com> wrote:
Hi everyone,
There is a proposal [1] (with implemented revision) to implement zero-initialising versions of malloc{,Bytes,Array,Array0}
- Add calloc and callocBytes to Foreign.Marshal.Alloc. - Add callocArray and callocArray0 to Foreign.Marshal.Array.
The benefit is that you can allocate required amount of memory and be certain that it will be cleared (set with zeroes) before you use it. Original discussion took a place in `fillBytes` [1] and was publicised on that mailing list [2].
Please share your thoughts.
Thank you.
[1] https://phabricator.haskell.org/D527 [2] https://phabricator.haskell.org/D461#11541 [3] https://www.haskell.org/pipermail/libraries/2014-November/024251.html
-- alex p
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On 2014-11-29 at 17:05:58 +0100, Oleksandr Petrov wrote:
There is a proposal [1] (with implemented revision) to implement zero-initialising versions of malloc{,Bytes,Array,Array0}
- Add calloc and callocBytes to Foreign.Marshal.Alloc. - Add callocArray and callocArray0 to Foreign.Marshal.Array.
The benefit is that you can allocate required amount of memory and be certain that it will be cleared (set with zeroes) before you use it.
+1 (Fwiw, it's not only a convenient combined operation but it also has potentially less overhead by requiring only a single FFI-call to calloc(3), instead of having to FFI-call twice into libc when doing malloc(3)+memset(3))
I'm also +1 for this addition.
On Sun, Nov 30, 2014 at 2:42 AM, Herbert Valerio Riedel
On 2014-11-29 at 17:05:58 +0100, Oleksandr Petrov wrote:
There is a proposal [1] (with implemented revision) to implement zero-initialising versions of malloc{,Bytes,Array,Array0}
- Add calloc and callocBytes to Foreign.Marshal.Alloc. - Add callocArray and callocArray0 to Foreign.Marshal.Array.
The benefit is that you can allocate required amount of memory and be certain that it will be cleared (set with zeroes) before you use it.
+1
(Fwiw, it's not only a convenient combined operation but it also has potentially less overhead by requiring only a single FFI-call to calloc(3), instead of having to FFI-call twice into libc when doing malloc(3)+memset(3))
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-- Regards, Austin Seipp, Haskell Consultant Well-Typed LLP, http://www.well-typed.com/
Not only that, calloc often comes from fresh 0-initialized memory that is
just allocated when forced in the memory manager, so it can often get
zeroed for free.
-Edward
On Sun, Nov 30, 2014 at 7:42 PM, Herbert Valerio Riedel
On 2014-11-29 at 17:05:58 +0100, Oleksandr Petrov wrote:
There is a proposal [1] (with implemented revision) to implement zero-initialising versions of malloc{,Bytes,Array,Array0}
- Add calloc and callocBytes to Foreign.Marshal.Alloc. - Add callocArray and callocArray0 to Foreign.Marshal.Array.
The benefit is that you can allocate required amount of memory and be certain that it will be cleared (set with zeroes) before you use it.
+1
(Fwiw, it's not only a convenient combined operation but it also has potentially less overhead by requiring only a single FFI-call to calloc(3), instead of having to FFI-call twice into libc when doing malloc(3)+memset(3))
_______________________________________________ Libraries mailing list Libraries@haskell.org http://www.haskell.org/mailman/listinfo/libraries
+1 here too additionally for GHCJS this is a no-brainer since ArrayBuffers (used for data storage when Addr# / Ptr is involved) are initialized to 0 on allocation, making calloc no more expensive than malloc. On Sat, Nov 29, 2014 at 5:05 PM, Oleksandr Petrov < oleksandr.petrov@gmail.com> wrote:
Hi everyone,
There is a proposal [1] (with implemented revision) to implement zero-initialising versions of malloc{,Bytes,Array,Array0}
- Add calloc and callocBytes to Foreign.Marshal.Alloc. - Add callocArray and callocArray0 to Foreign.Marshal.Array.
The benefit is that you can allocate required amount of memory and be certain that it will be cleared (set with zeroes) before you use it. Original discussion took a place in `fillBytes` [1] and was publicised on that mailing list [2].
Please share your thoughts.
Thank you.
[1] https://phabricator.haskell.org/D527 [2] https://phabricator.haskell.org/D461#11541 [3] https://www.haskell.org/pipermail/libraries/2014-November/024251.html
-- alex p
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+1, very sensible addition.
On 09:24, Sun, Nov 30, 2014 Luite Stegeman
+1 here too
additionally for GHCJS this is a no-brainer since ArrayBuffers (used for data storage when Addr# / Ptr is involved) are initialized to 0 on allocation, making calloc no more expensive than malloc.
On Sat, Nov 29, 2014 at 5:05 PM, Oleksandr Petrov < oleksandr.petrov@gmail.com> wrote:
Hi everyone,
There is a proposal [1] (with implemented revision) to implement zero-initialising versions of malloc{,Bytes,Array,Array0}
- Add calloc and callocBytes to Foreign.Marshal.Alloc. - Add callocArray and callocArray0 to Foreign.Marshal.Array.
The benefit is that you can allocate required amount of memory and be certain that it will be cleared (set with zeroes) before you use it. Original discussion took a place in `fillBytes` [1] and was publicised on that mailing list [2].
Please share your thoughts.
Thank you.
[1] https://phabricator.haskell.org/D527 [2] https://phabricator.haskell.org/D461#11541 [3] https://www.haskell.org/pipermail/libraries/2014-November/024251.html
-- alex p
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_______________________________________________ Libraries mailing list Libraries@haskell.org http://www.haskell.org/mailman/listinfo/libraries
participants (6)
-
Austin Seipp -
Edward Kmett -
Herbert Valerio Riedel -
John Lato -
Luite Stegeman -
Oleksandr Petrov