The Linux mmap trap got me AGAIN! ARRRRRRGGGGGGGHHHHHHH... https://www.youtube.com/watch?v=KjmjqlOPd6A …
-
-
-
Replying to @alexyanov
The returned memory from mmap is all mapped to a single 4k page, no matter how much you ask for. It does not actually commit the memory until you try to write to it. There are many ways this can bite you if you don't know about it!
2 replies 0 retweets 2 likes -
Replying to @cmuratori @alexyanov
I can't think of an example of this hurting other than having to pay the price of commiting on write instead of mmap call. Hint? (were you timing things?)
1 reply 0 retweets 0 likes
There are at least two ways it can hurt you - one is timing reads, and one is your app thinking an allocation succeeded when actually it failed, and then it will simply fault on the write. That last one is particularly bad for programs that are trying to be careful.
Loading seems to be taking a while.
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.