Message185368
> Through fork, yes, but "shared" rather than "copy-on-write".
There's a subtlety: because of refcounting, just treating a COW object
as read-only (e.g. iteratin on the array) will trigger a copy
anyway...
> I assume you mean "shared memory" and shm_open(), not "semaphores" and
> sem_open().
Yes ;-)
> I don't think shm_open() really has any advantages over
> using mmaps backed by "proper" files (since posix shared memeory uses up
> space in /dev/shm which is limited).
File-backed mmap() will incur disk I/O (although some of the data will
probably sit in the page cache), which would be much slower than a
shared memory. Also, you need corresponding disk space.
As for the /dev/shm limit, it's normally dimensioned according to the
amount of RAM, which is normally, which is in turn dimensioned
according to the working set. |
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Date |
User |
Action |
Args |
2013-03-27 19:27:30 | neologix | set | recipients:
+ neologix, pitrou, mrjbq7, sbt |
2013-03-27 19:27:30 | neologix | link | issue17560 messages |
2013-03-27 19:27:30 | neologix | create | |
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