One SVN repository or many?

Question

If you have multiple, unrelated projects, is it a good idea to put them in the same repository?

myRepo/projectA/trunk
myRepo/projectA/tags
myRepo/projectA/branches
myRepo/projectB/trunk
myRepo/projectB/tags
myRepo/projectB/branches

or would you create new repositories for each?

myRepoA/trunk
myRepoA/tags
myRepoA/branches
myRepoB/trunk
myRepoB/tags
myRepoB/branches

What are the pros and cons of each? All that I can currently think of is that you get mixed revision numbers (so what?), and that you can't use svn:externals unless the repository is actually external. (i think?)

The reason I ask is because I'm considering consolidating my multiple repos into one, since my SVN host has started charging per repo.

Answer 1

Similar to Blade's suggestion about sharing files, here is a slightly easier, yet less flexible solution. I setup ours like so:

• /var/svn/
• /var/svn/bin
• /var/svn/repository_files
• /var/svn/svnroot
• /var/svn/svnroot/repos1
• /var/svn/svnroot/repos2
• ...

In "bin", I keep a script called svn-create.sh which will do all of the setup work of creating an empty repository. I also keep the backup script there.

In "repository_files", I keep common "conf" and "hooks" directories that all of the repositories have sym links to. Then, there's only one set of files. This does eliminate the ability to have granular, per-project access without breaking the links, though. That was not a concern where I set this up.

Last, I keep the main directory /var/svn under source control ignoring everything in svnroot. That way the repository files and scripts are under source control as well.

#!/bin/bash

# Usage:
# svn-create.sh repository_name

# This will:
# - create a new repository
# - link the necessary commit scripts
# - setup permissions
# - create and commit the initial directory structure
# - clean up after itself

if [ "empty" = ${1}"empty" ] ; then
  echo "Usage:"
  echo "    ${0} repository_name"
  exit
fi

SVN_HOME=/svn
SVN_ROOT=${SVN_HOME}/svnroot
SVN_COMMON_FILES=${SVN_HOME}/repository_files
NEW_DIR=${SVN_ROOT}/${1}
TMP_DIR=/tmp/${1}_$$

echo "Creating repository: ${1}"

# Create the repository
svnadmin create ${NEW_DIR}

# Copy/Link the hook scripts
cd ${NEW_DIR}
rm -rf hooks
ln -s ${SVN_COMMON_FILES}/hooks hooks

# Setup the user configuration
cd ${NEW_DIR}
rm -rf conf
ln -s ${SVN_COMMON_FILES}/conf conf

# Checkout the newly created project
svn co file://${NEW_DIR} ${TMP_DIR}

# Create the initial directory structure
cd ${TMP_DIR}
mkdir trunk
mkdir tags
mkdir branches

# Schedule the directories addition to the repository
svn add trunk tags branches

# Check in the changes
svn ci -m "Initial Setup"

# Delete the temporary working copy
cd /
rm -rf ${TMP_DIR}

# That's it!
echo "Repository ${1} created. (most likely)"

Answer 2

For your specific case one(1) repository is perfect. You will save a lot of money. I always encourage people to use a single repository. Because it is similar to a single filesystem: It is easier

• You will have a single place where you look for code
• You will have a single authorisation
• You will have a single commit number(ever tried to build a project which is spread over 3 repos?)
• You can better reuse common libraries and track your progress in these libs(svn:externals are PITA and will not solve all problems)
• Projects planned as fully different items, can grow together and share functions and interfaces. This will be very difficult to achieve in multiple repos.

There is a single point for multiple repositories: administration of huge repos is uncomfortable. Dumping/loading huge repos takes a lot of time. But as you do not do any administration, I think it will not be your concern ;)

SVN scales very well with bigger repositories, there is no slowdown even on huge (>100GB) repositories.

So you will have less hassle with a single repository. But you really should think about the repo layout!

Answer 3

If you plan to or use tool like trac wich integrate with SVN, it makes more sense to use one repo per project.

Answer 4

I would use multiple repositories. In addition to the user access issue, it also makes backup and restore easier. And if you find yourself in a position where somebody wants to pay you for your code (and its history), it's easier to give them just a repository dump.

I would suggest that consolidating repositories just because of the charging policies of your hosting provider is not a very good reason.

Answer 5

Similar to mlambie's of using a single repo, but went bit further with the folder structure to easily zoom to particular type of projects - web html based projects vs. cs (C#) vs. sql (SQL create/execute scripts) vs. xyz (Domain Specific Languages like afl (AmiBroker Formula Language) or ts (TradeStation)):

/<src|lib>/<app-settings|afl|cs|js|iphone|sql|ts|web>/<ClientName>/<ProjectName>/<branches|tags>

Note, I have trunk live within branches as I treat it as the default branch. The only pain sometimes is when you want to quickly create another project you need to build out the ProjectName/branches|tags structure. I use app-settings simply as place to keep specific Apps settings files in repo so easily shareable to others (and substitute ClientName to VendorName and ProjectName to AppName in this folder structure; and the branches|tags can be useful to tag settings across different major versions of vendor products too).

Welcome to any comments on my structure - I recently changed it to this and so far pretty happy but sometimes find it burdensome to maintain branches|tags structures per project - particularly if the project is simply a project setup simply to Unit Test another project.

Answer 6

Be aware that when making your decision, many SVN repos can share the same config file.

Example (taken from link above):

In shell:

$ svn-admin create /var/svn/repos1
$ svn-admin create /var/svn/repos2
$ svn-admin create /var/svn/repos3

File: /var/svn/repos1/conf/svnserve.conf

[general]
anon-access = none # or read or write
auth-access = write
password-db = /var/svn/conf/passwd
authz-db = /var/svn/conf/authz
realm = Repos1 SVN Repository

File: /var/svn/conf/authz

[groups]
group_repos1_read = user1, user2
group_repos1_write = user3, user4
group_repos2_read = user1, user4

### Global Right for all repositories ###
[/]
### Could be a superadmin or something else ###
user5 = rw

### Global Rights for one repository (e.g. repos1) ###
[repos1:/]
@group_repos1_read = r
@group_repos1_write = rw

### Repository folder specific rights (e.g. the trunk folder) ###
[repos1:/trunk]
user1 = rw

### And soon for the other repositories ###
[repos2:/]
@group_repos2_read = r
user3 = rw