Opened 4 years ago
Last modified 3 weeks ago
#31804 assigned New feature
Parallelize database cloning process
Reported by: | Ahmad A. Hussein | Owned by: | Ahmed Ibrahim |
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Component: | Database layer (models, ORM) | Version: | dev |
Severity: | Normal | Keywords: | parallel, mysqlpump |
Cc: | Triage Stage: | Accepted | |
Has patch: | yes | Needs documentation: | no |
Needs tests: | yes | Patch needs improvement: | no |
Easy pickings: | no | UI/UX: | no |
Description (last modified by )
Parallelizing database cloning processes would yield a nice speed-up for running Django's own test suite (and all django projects that use the default test runner)
So far there are three main ways I see we can implement this:
- Use a multiprocessing pool at the setup_databases level that'll create workers which run
clone_test_db
for each method
- Use a pool at the
clone_test_db
level which parallelizes the internal
_clone_test_db
call
- Scrap parallelizing the cloning in general, but parallelizing the internals of specific backends (at least MySQL fits here)
In the first two options, we'd have to refactor MySQL's cloning process since it has another call to _clone_db
. We have to because otherwise we'd have a dump being created inside of each parallel process, slowing the workers greatly.
In the last option, we could consider using mysqlpump instead of mysqldump for both exporting the database and restoring it. The con of this approach is that it isn't general enough to apply to the other backends.
Oracle's cloning process(although not merged in the current master) has internal support for option 3 (users can specify a PARALLEL variable to speed-up expdp/impdp utilities), and it can also use the first two options.
The major con though with the first two options is forcing parallelization
Change History (7)
comment:1 by , 4 years ago
Owner: | changed from | to
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comment:2 by , 4 years ago
Description: | modified (diff) |
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comment:3 by , 4 years ago
Triage Stage: | Unreviewed → Accepted |
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comment:5 by , 15 months ago
Owner: | removed |
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Status: | assigned → new |
comment:7 by , 3 weeks ago
Has patch: | set |
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Needs tests: | set |
Hi Ahmad. Yes: if you can get this going super.
One thing that's been bugging me about #31169 is how slow the DB cloning appears on Windows. (I need to measure exact times...) So if we can speed that up, it would be a big win.
Thanks.