Yes, you're right in the general case.
But a solution to that general problem will take time to be implemented (time I lack at the moment, sadly) and if the main gain is a few % because it's writing the version file and the metadata for methods which are the "slow" factors, then we'll have worked
hard for nothing.
If you want to help, I'd really like to see either 2- or 3- confirmed. I can produce a special gitfiletree to remove writing the metadata, that you can try on a large project temporary copy; if the slow writing (and reading) is confirmed, then this is 3-
(But I'm leaving on a trip tomorrow early, so I have no idea of when I'll have the time to do that :( ).
Thierry
Le 11/12/2013 16:44, Sebastian Sastre a �crit :
Without entering in details, a cause for slow package write is dumping
all every time.
For that strategy, we already have the image save which is magically fast.
So, if we make something to scan the code and write only when it's
different from what's on disk, then we would be preventing tons of
redundant writes
sebastian <https://about.me/sebastianconcept>
o/
On Dec 11, 2013, at 1:43 PM, Goubier Thierry <thierry.goubier@cea.fr
<mailto:thierry.goubier@cea.fr>> wrote:
Le 11/12/2013 16:27, Esteban Lorenzano a �crit :
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
<estebanlm@gmail.com <mailto:estebanlm@gmail.com>
<mailto:estebanlm@gmail.com>> 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
<thierry.goubier@cea.fr
<mailto:thierry.goubier@cea.fr><mailto:thierry.goubier@cea.fr>> 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 �crit :
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
<sebastian@flowingconcept.com
<mailto:sebastian@flowingconcept.com>
<mailto:sebastian@flowingconcept.com>
<mailto:sebastian@__flowingconcept.com
<mailto:sebastian@flowingconcept.com>>> 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
<sebastian@flowingconcept.com
<mailto:sebastian@flowingconcept.com>
<mailto:sebastian@flowingconcept.com>
<mailto:sebastian@__flowingconcept.com
<mailto:sebastian@flowingconcept.com>>>
wrote:
Hi Thierry
On Dec 11, 2013, at 12:43 PM, Goubier Thierry
<thierry.goubier@cea.fr
<mailto:thierry.goubier@cea.fr>
<mailto:thierry.goubier@cea.fr>
<mailto:thierry.goubier@cea.fr
<mailto:thierry.goubier@cea.fr>__>> 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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