Re: Can we remove DAV-props/WC-props from the code now?

On Thu, Jan 31, 2013 at 3:28 PM, Bert Huijben <bert_at_qqmail.nl> wrote:
>
>
>> -----Original Message-----
>> From: Ivan Zhakov [mailto:ivan_at_visualsvn.com]
>> Sent: donderdag 31 januari 2013 11:56
>> To: C. Michael Pilato
>> Cc: Julian Foad; Subversion Development; BertHuijben
>> Subject: Re: Can we remove DAV-props/WC-props from the code now?
>>
>> On Thu, Jan 31, 2013 at 12:18 AM, Ivan Zhakov <ivan_at_visualsvn.com> wrote:
>> > On Wed, Jan 30, 2013 at 10:20 PM, C. Michael Pilato <cmpilato_at_collab.net>
>> wrote:
>> >> On 01/30/2013 11:46 AM, Julian Foad wrote:
>> >>> It would be awesome if we can now completely remove the code
>> supporting
>> >>> 'DAV props' aka 'WC props' in the client side, if it is no longer needed
>> >>> there.
>> >>>
>> >>> I know little about it myself, but on IRC, Bert said [1]:
>> >>>
>> >>> "I would hope we can ignore WC/DAV props. And if somebody suggests
>> it I
>> >>> would be +1 on removing them now completely from our client. (The
>> skelta
>> >>> update in serf for old style servers makes them unnecessary).
>> >>>
>> >>> I think the reason to keep them was serf without http v2, but that
>> should
>> >>> be fixed. Using a subversion 1.0 server (pre skelta) would get slower,
>> >>> but I don't think anybody cares about that.
>> >>>
>> >>> It still works ok.
>> >>>
>> >>> The repository diff already makes sure dav props won't show up during
>> >>> merge. (I think since 1.7)
>> >>>
>> >>> Dav props should nowdays only be written by the update editor, and
>> read
>> >>> by some callback api that is initialized with ra sessions. "
>> >>
>> >> libsvn_ra_serf today only interacts with a single DAV prop:
>> >> SVN_RA_SERF__WC_CHECKED_IN_URL. That property is...
>> >>
>> >> ...invalidated:
>> >> - during all switch operations.
>> >> ...read:
>> >> - during non-HTTP-v2, skelta-mode updates.
>> >> - during non-HTTP-v2 commits.
>> >> ...written:
>> >> - during non-HTTP-v2 commits.
>> >>
>> > It would be great to remove WC props support from all layers in 1.8.
>> > They are mostly superseded by other things:
>> > - 1.8 client against pre-1.8 server uses non-skelta bulk-mode for updates
>> > - 1.8 client and 1.8 server uses HTTPv2
>> > - runtime baseline-information cache implemented in svn 1.7 stores
>> > information about checked-in URL for revisions. So checked-in URL will
>> > be requested only once for each revision during commit to pre-1.7
>> > server
>> >
>> I've tested svn 1.8 commit to svn 1.6 server: disabling wc-props
>> results one extra PROPFIND request for each changed file compared to
>> wc-props enabled client. I think that one extra request is ok. Users
>> should upgrade server if they want performance.
>
> Why this extra request per node?
> (Assuming it is an update/checkout)
>
Client request checked-in URL to CHECKOUT proper resource. This
request happens only during commit, not on update/checkout.

-- 
Ivan Zhakov