Volute transfer
Options for transferring
Volute from
GoogleCode to
GitHub.
Headline figures, based on disc usage
volute-complete - 825M
Svn checkout of everything in the repository.
svn checkout https://volute.googlecode.com/svn/trunk/ volute-complete
du -h volute-complete > complete-original.txt
volute-noextern - 764M
Svn checkout, without resolving the extern references.
svn checkout --ignore-externals https://volute.googlecode.com/svn/trunk/ volute-noextern
du -h volute-noextern > noextern-original.txt
volute-export - 391M
Svn export, a snapshot of the current state with no commit history.
svn export --ignore-externals https://volute.googlecode.com/svn/trunk/ volute-export
du -h volute-export > export-original.txt
Of the 391M in the exported snapshot, the top 8 projects are :
- theory 220M
- dm 126M
- registry 26M
- grid 6M
- vocabularies 3M
- samp 3M
- votable 2M
- ivoapub 2M
Maximal transfer
If we just press the 'export to GitHub' button, then everything will get
transferred, including the commit history.
I have seen this work on a
small project, and everything just worked.
On a large project like ours the process will probably take a while.
With a total size of 825M we are close to the GitHub 1Gbyte per repository
limit, which may cause problems later on.
The only unusual thing to watch for is that the email telling you the
process has completed will be sent to the email address linked to your
GitHub account, not to your Google account.
See:
GitHubExporter
IVOA organization
If we want our GitHub repository to be owned by the
IVOA organization in GitHub, do the transfer
to your private account, and then transfer the repository afterwards.
See:
Migrate to an Organization
Commit history
It is important to note that the automated 'export to GitHub' tool is the
only realistic way to preserve the commit history of the svn reposiroty.
All of the alternative suggestions outlined below rely on a manual process
of exporting the contents to a local copy and then importing some or all
of it into one or more GitHub repositories. If we decide to go for one
of these alternatives then it is not practical to try to preserve the svn
commit history.
Snapshot transfer
If we skip the svn history and just take a snapshot of where we are now,
then we have less than 400M to transfer.
We would have to do the transfer manually, exporting a local copy from svn,
and then importing it into a new GitHub repository.
git clone https://github.com/YOUR-USERNAME/YOUR-REPOSITORY local-repo
svn export --ignore-externals https://volute.googlecode.com/svn/trunk/ local-repo
pushd local-repo
git add .
git commit -m 'Initial import from svn'
git push
popd
Space limits
GitHub don't have hard and fast limits on the size of a repository.
We *recommend* repositories be kept under 1GB each. This limit is easy
to stay within if large files are kept out of the repository. If your
repository exceeds 1GB, you might receive a polite email from GitHub
Support requesting that you reduce the size of the repository to bring
it back down.
(emphasis mine)
See:
What is my disk quota ?
I contacted GitHub to see if there would be an issue with us using more
than 1Gbyte of space.
I got the following reply from a member of their help team :
Hi Dave,
Thanks for reaching out! We strongly recommend keeping repositories under
1GB in size. Additionally, to ensure that repository performance is optimal,
only files less than 100MB in size can be pushed to GitHub.com.
More information about this can be found here:
https://help.github.com/articles/what-is-my-disk-quota
The good news is that in order to make working with large files better,
we recently published an extension to Git called Git Large File Storage,
and support for Git LFS is currently in early access on GitHub.com.
You can check it out at http://git-lfs.github.com and sign up for early
access at https://github.com/early_access/large_file_storage
I hope this information helps, please let us know if you have any questions!
Cheers,
Rachel
Large files
I suspect that due to the way that we use volute, the
Large File Storage extension will be of
limited value to us.
In the current version of the Git LFS extension you can't select which
files should be stored separately based on file size. The file selection
criteria is based purely on file path and type.
A number of people have been asking for selection by size, but it does not
look like it will be available soon.
This means that in order for it to be useful in reducing the size of our
repository, we would need to identify which files we wanted to be handles
using the LFS extension
before they were added to the repositiory.
In reality, some of our uses would be extremely careful about making sure
every
pdf
and
doc
file in their project was listed, even the ones that
were less than 1Mbyte.
Other users would just want to be able to commit and push a whole directory
tree and leave it up to the software to sort out which files need to be
handled differently.
GitHub has a maximum file size limit of 100M per file.
The LFS extension was designed to enable Git to handle things like binary
image files, e.g.
jpeg
,
png
,
svg
.
Using the file path and type to identify which files should be treated
differently.
Looking the files in the current volute repository, we have a wide variety
of different file types and sizes, and it would be difficlut to define a
reliable selection criteria to identify which files should be handled by LFS.
- We have no files larger than 100M bytes.
- We have no files larger than 50M bytes.
- We have four files larger than 10M bytes, all of them in the theory project.
- projects/theory/snap/simtap/PDR143/PDR143-2.vo-urp
- projects/theory/snap/simtap/PDR143/html/PDR143-2.html
- projects/theory/snap/simtap/PDR143/tap/PDR143-2_tap_tableset.xml
- projects/theory/snap/simtap/PDR143/tap/PDR143-2_votable.xml
- We have a few files larger than 5M bytes, most of them in the theory project.
- projects/dm/vo-dml/libs/eclipselink.jar
- projects/theory/snap/simtap/PDR143/PDR143-2.vo-urp
- projects/theory/snap/simtap/PDR143/html/PDR143-2.html
- projects/theory/snap/simtap/PDR143/tap/PDR143-2_tap_tableset.xml
- projects/theory/snap/simtap/PDR143/tap/postgres/PDR143-2_create_tap_schema.sql
- projects/theory/snap/simtap/PDR143/tap/mssqlserver/PDR143-2_create_tap_schema.sql
- projects/theory/snap/simtap/PDR143/tap/PDR143-2_votable.xml
- projects/theory/snap/simtap/PDR143/tap/PDR143-2_vodataservice.xml
- projects/theory/snapdm/input/other/sourceDM/IVOACatalogueDataModel.pdf
- We have 70 files larger than 1M bytes.
- Everything else is smaller than 1M byte.
Note that many of our largest files are 10Mbyte+
html
and
xml
files,
presumably generated by our modelling tools.
Equally, some of our smallest files are
html
and
xml
files, and we would not
want any of the
html
and
xml
source files for our standards documents
to be stored externally as binary files.
Project types
Looking at the current contents volute, we have four different project types.
Theory projects
It looks like the three theory projects contain a relativley small number
of human edited source files, and the majority of the space is taken up by
machine generated files.
- projects/theory - 220M
- snap - 108M
- snapdm - 109M
- simdal - 3.3M
There is a good case for exporting each of the three theory projects as
separate GitHub repositories.
Even without using the LFS extension to manage the larger files, these
projects would all be under the recomended 1Gbyte per repository limit.
Data models
Four of the data model projects are directly related to the standard
documents defining the corresponding data model.
The majority of the space is taken up by a mixture of medium sized (1M <
s < 10M)
doc
,
pdf
and
png
files.
The fith data model project is for the VO Data Modelling Language, VO-DML.
This project accounts for over 100M of the 126M of space used by the data
model projects, and is the third largest project in the volute repository.
Again, the majority of the space is taken up by a mixture of medium sized
(1M < s < 10M)
doc
,
pdf
and
png
files.
Although this project is related to the VO-DML and UTYPE specifications,
there is a case for exporting it as a separate separate GitHub repository.
In addition to the documents for the VO-DML and UTYPE specifications the
vo-dml project also contains definitions of the models themselves along with
the source code for the tools for validating the models and for building
derived data products from them.
VOSpace service
We have one project that contains code for a program, donated by Rick Wagner
at UC San Diego.
- projects/grid/vospace/php_endpoint
- size : 1.5M
- type : PHP web service
- lang : php
= PHP VOSpace Endpoint =
VOSpace endpoint building on top of the [http://www.irods.org iRODS] client, Prods.
Requires Prods, which is part of the iRODS distributions (under clients). Also uses
[http://simpletest.sf.net SimpleTest] for unit tests. Configure the locations in config.inc.
Rick Wagner
http://lca.ucsd.edu/projects/rpwagner
rwagner@physics.ucsd.edu
As a self-contained source code project there is a case good case for
exporting this project as separate GitHub repository of its own.
Vocabularies
The vocabularies project contains the build tree for the IVOA vocabulary
SKOS files.
Although this project is relatively small, 3.4M, it is not directly related
to an IVOA document or standard.
As a self-contained source code project there is a case good case for
exporting this project as separate GitHub repository of its own.
Documents and standards
Everything else in our repository are either source text for our documents
or tools for creating documents.
If we wanted to we could use the LFS extension to process all of the
doc
,
pdf
and
jpeg
files separately.
However, this would not reduce the size of a local clone of the repository,
nor the time it would take to download it.
Proposed structure
If we take a copy of the exported snapshot and split out the projects
identified above as candidates for separate GitHub repositories.
mkdir github-repos
pushd github-repos
cp -r ../volute-export local-temp
mv local-temp/projects/theory ivoa-theory
mv local-temp/projects/dm/vo-dml ivoa-dml
mv local-temp/projects/vocabularies ivoa-vocabularies
mv local-temp/projects/grid/vospace/php_endpoint php-vospace
mv local-temp/projects ivoa-documents
popd
du -h github-repos > github-repos.txt
The we get the following set of candidate GitHub repositories:
- github-repos - 391M
- php-vospace - 1.5M
- ivoa-vocabularies - 3.4M
- ivoa-documents - 66M
- ivoa-dml - 101M
- ivoa-theory - 220M
If we split the three theory projects into separate GitHub repositories,
then we get the following:
- github-repos - 391M
- php-vospace - 1.5M
- ivoa-vocabularies - 3.4M
- ivoa-documents - 66M
- ivoa-dml - 101M
- ivoa-snap - 108M
- ivoa-snapdm - 109M
- ivoa-simdal - 3.3M
Historical documents
It would be possible to further reduce the size of the ivoa-documents GitHub repository
by excluding the historical versions of the documents stored in the current repository.
References