Re: [naviserver-devel] Upload Progress

[Zoran V. <zv...@ar...>]

Am 02.01.2006 um 12:06 schrieb Zoran Vasiljevic:

>
> Am 02.01.2006 um 04:43 schrieb Vlad Seryakov:
>
>> Tried it, nsd started crashing and i am guessing that the problem  
>> is combination of aio_write and mmap.
>> When is start spooling, i just submit aio_write and return  
>> immediately, so there are a lot of quick aio_write calls. By the  
>> time i reach mmap, it looks like it's always ahead of actual  
>> writing, so even when i am trying to check aio_error/aio_fsync in  
>> the NsGetRequest, i still get SIGBUS/SIGSEGV when i access reqPtr- 
>> >content, looks like mmap and aio_write are out of sync. And there  
>> is no way to wait until all file buffers will be flushed, so  
>> manual separate thread implementation could be the only portable  
>> solution. Or i just do not understand aio_xxx things completely.
>
> Hm... the idea is to mmap the file when all is read from the client.
> So you'd have to aio_write into the file until all is received, then
> at some point check the aio_status of the write (non-blocking) and
> when it's done, revert to mmap the file. I do not believe you can
> mix the aio_ with mmap.

What I still do not know is: if you are allowed to issue multiple
outstanding aio_writes one after another... It might be that you
need to check wether the first aio_write is done before you attempt
the next one.

Zoran