Le 11/12/2013 16:27, Esteban Lorenzano a écrit :
ah, and IMHO the problem is not about reading... is about writing (if it
has to write the metadata each time...).

But, personnaly, I don't know if this is the reason for the lack of performance...

I have three hypothesis for Sebastian problem:
1 - Slow read time for version metadata
- Confirmed because of the 16 seconds wait time for reading the package metadata in the repository browser.
2 - Slow metadata write
3 - Slow package write

I have an implemented solution for 1-, a very easy to implement for 2-, and none yet for 3-

So I'd really like to check if 3- is confirmed ;)

Thierry


Esteban


On Wed, Dec 11, 2013 at 4:24 PM, Esteban Lorenzano <[email protected]
<mailto:[email protected]>> wrote:

    Thierry, I know there is a working version... let me search...

    (5 mins later)


    here:

    https://github.com/rjsargent/CypressReferenceImplementation

    Dale says Richard made a metadata-less version.

    We should take a look at that.

    Esteban


    On Wed, Dec 11, 2013 at 4:28 PM, Goubier Thierry
    <[email protected] <mailto:[email protected]>> wrote:

        Esteban, Sebastian,

        In the filetree code, you will find a format without metadata,
        but it's not in use anymore.

        If you use gitfiletree, it will write the metadata for
        compatibility reasons with filetree, but it will never read it back.

        I'm pushing code to make filetree robust to absence of metadata,
        but I haven't worked on it for a while.

        gitfiletree has solved the problem of a slow metadata read. It
        does not solve any performance problem associated with writing, yet.

        Thierry

        Le 11/12/2013 16:12, Esteban Lorenzano a écrit :

            I know there is a version of filetree without metadata (more
            compelling
            for projects that will never use other formats).
            Dale told me that there was a preview somewhere, but I
            didn't tested yet
            (lack of time) and now I cannot find the mail...
            Dale, can you re-send the link?

            cheers,
            Esteban


            On Wed, Dec 11, 2013 at 4:08 PM, Sebastian Sastre
            <[email protected]
            <mailto:[email protected]>
            <mailto:sebastian@__flowingconcept.com
            <mailto:[email protected]>>> wrote:

                 I should breath before I type, but you probably already
            got that I
                 meant /redundant writes/ (not reads)...


                 Anyway.. I was talking with Esteban and he mentions
            some kind of
                 compatibility metadata.

                 If I'm going to give a leap of faith to filetree repos
            to save code
                 why should I care about mcz compatibility? Paying a
            toll for no
                 reason is evil.

                 Maybe we could make that optional so those who don't
            extract value
                 from that feature can opt-out?

                 sebastian <https://about.me/__sebastianconcept
            <https://about.me/sebastianconcept>>


                 o/





                 On Dec 11, 2013, at 12:44 PM, Sebastian Sastre
                 <[email protected]
            <mailto:[email protected]>
            <mailto:sebastian@__flowingconcept.com
            <mailto:[email protected]>>>
                 wrote:

                     Hi Thierry

                     On Dec 11, 2013, at 12:43 PM, Goubier Thierry
                     <[email protected]
                <mailto:[email protected]>
                <mailto:[email protected]
                <mailto:[email protected]>__>> wrote:


                             I have packages (in the order of hundreds
                        of classes) and save
                             delays
                             and package click delays are starting to
                        demand patience in a
                             way that
                             doesn't feel like the right path


                         Which operations ? I didn't remember noticing
                    much with 179
                         classes on a laptop without a SSD.


                     choose one. Just for clicking the package that will
                should you
                     UUID, version and author I need to wait ~16
                seconds. Sounds like a
                     lot of overhead for reading a small .json file.

                     But the write is the most worrisome


                             All that is with a SSD disk, otherwise save
                        delays would be
                             /way/ beyond
                             unacceptable


                         I'd like to know more, and understand the
                    reason, for sure. As
                         far as I know, filetree will rewrite the whole
                    package to disk
                         everytime... and maybe optimising that could be
                    the solution.


                     Well, that explains a lot. Writing all every time
                is the lazy
                     thing that's okay for a prototype and temporary
                code in a proof of
                     concept but that massive redundant reads certainly
                doesn't sounds
                     like pro software. Specially for SSD's which has a
                limited
                     quantity of writes


                         Thierry

                             sebastian
                        <https://about.me/__sebastianconcept
                        <https://about.me/sebastianconcept>>

                             o/






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