Re: pg_dump -Fd and compression level

>On Sat, Jul 25, 2015 at 9:56 PM, Andrew Dunstan <andrew@dunslane.net> wrote:
>>
>> On 07/25/2015 03:20 AM, Andrew Dunstan wrote:
>>>
>>>
>>> On 07/25/2015 02:34 AM, Marc Mamin wrote:
>>>>
>>>>
>>>>> Andrew Dunstan <andrew@dunslane.net> writes:
>>>>>>
>>>>>> Hmm. Yeah. It looks like commit
>>>>>> a7ad5cf0cfcfab8418000d652fa4f0c6ad6c8911
>>>>>> changed from using the default compression for libz to using the
>>>>>> compression set in pg_dump options, which defaults to 0. This actually
>>>>>> seems like the right thing to do, but it certainly should have been
>>>>>> called out much more forcefully in release notes, and arguably should
>>>>>> not have been changed in stable releases. Not sure what we do about it
>>>>>> now.
>>>>
>>>> really 0? wouldn't that mean no compression at all?
>>>
>>>
>>> No, that's not right either. The default should be Z_DEFAULT_COMPRESSION,
>>> so we shouldn't actually see a difference in the default case. And it is
>>> definitely compressing some. So I'm now puzzled by what you're seeing.
>>>
>>>
>>
>>
>> OK, I have got this worked out. I'll have a bug fix shortly.
>
>So you are basically planning to switch to Z_BEST_SPEED instead of
>Z_DEFAULT_COMPRESSION where needed for the default code path?
>--
>Michael

It looks like Z_DEFAULT_COMPRESSION was the used value before, and from the source code I guess this should still be
thecase. 

From a quick testing, it now behaves as if the minus sign from Z_DEFAULT_COMPRESSION is lost on the way,
resulting in -Z1. this might indicate that Z_DEFAULT_COMPRESSION is parsed like the command line argument.
e.g. pg_dump -Z-2 is like pg_dump -Z2

Marc