Re: BUG #7534: walreceiver takes long time to detect n/w breakdown

On 15.10.2012 19:31, Fujii Masao wrote:
> On Mon, Oct 15, 2012 at 11:27 PM, Heikki Linnakangas
> <hlinnakangas(at)vmware(dot)com> wrote:
>> On 15.10.2012 13:13, Heikki Linnakangas wrote:
>>>
>>> Oh, I didn't remember that we've documented the specific structs that we
>>> pass around. It's quite bogus anyway to explain the messages the way we
>>> do currently, as they are actually dependent on the underlying
>>> architecture's endianess and padding. I think we should refactor the
>>> protocol to not transmit raw structs, but use pq_sentint and friends to
>>> construct the messages. This was discussed earlier (see
>>>
>>> http://archives.postgresql.org/message-id/4FE2279C.2070506@enterprisedb.com)
>>> I think there's consensus that 9.3 would be a good time to do that as we
>>> changed the XLogRecPtr format anyway.
>>
>>
>> This is what I came up with. The replication protocol is now
>> architecture-independent. The WAL format itself is still
>> architecture-independent, of course, but this is useful if you want to e.g
>> use pg_receivexlog to back up a server that runs on a different platform.
>>
>> I chose the int64 format to transmit timestamps, even when compiled with
>> --disable-integer-datetimes.
>>
>> Please review if you have the time..
>
> Thanks for the patch!
>
> When I ran pg_receivexlog, I encountered the following error.

Yeah, clearly I didn't test this near enough...

I fixed the bugs you bumped into, new version attached.

> + hdrlen = sizeof(int64) + sizeof(int64) + sizeof(int64);
> + hdrlen = sizeof(int64) + sizeof(int64) + sizeof(char);
>
> These should be macro, to avoid calculation overhead?

The compiler will calculate this at compilation time, it's going to be a
constant at runtime.

- Heikki