Re: Syslets, Threadlets, generic AIO support, v6

[Eric Dumazet <dada1@cosmosbay.com>]

Davide Libenzi a écrit :
> On Wed, 30 May 2007, Linus Torvalds wrote:
> 
>>> And then the semantics: do these descriptors should show up in
>>> /proc/self/fd?  Are there separate directories for each namespace?  Do
>>> they count against the rlimit?
>> Oh, absolutely. The'd be real fd's in every way. People could use them 
>> 100% equivalently (and concurrently) with the traditional ones. The whole, 
>> and the _only_ point, would be that it breaks the legacy guarantees of a 
>> dense fd space.
>>
>> Most apps don't actually *need* that dense fd space in any case. But by 
>> defaulting to it, we wouldn't break those (few) apps that actually depend 
>> on it.
> 
> I agree. What would be a good interface to allocate fds in such area? We 
> don't want to replicate syscalls, so maybe a special new dup function?
> 

If the deal is to be able to get faster open()/socket()/pipe()/... calls by 
not finding the first 0 bit in a huge bitmap, a better way would be to have a 
flag in struct task, reset to 0 at exec time.

A new syscall would say : This process is OK to receive *random* fds.