Speed up your backups by compressing and posting in parallel

Its pretty typical to have data stores that are several hundreds of GB’s in size and need to be posted offsite.

At weheartit our database is ~1/2 TB uncompressed and the old method of compressing and posting to S3 took 9 hours and rarely completed.

I was able to speed up this process and now it completes in < 1 hour.
53 minutes in fact.

For compression I used pbzip2 instead of gzip.

This is how I am using it along with percona’s xtrabackup.

innobackupex --user root --password $PASSWORD --slave-info --safe-slave-backup --stream=tar ./ | pbzip2 -f -p40 -c  > $BACKUPDIR/$FILENAME

The backup and compression only takes 32 minutes and compresses it from 432GB to 180GB

Next comes speeding up the transfer to S3.

In November of 2010 amazon added this feature to S3 but for some reason this functionality hasn’t been added to s3cmd.
Instead I am using s3 multipart upload
Thanks David Arther!

This is how I am using it.

/usr/local/bin/s3-mp-upload.py --num-processes 40 -s 250 $BACKUPDIR/$FILENAME $BUCKET/$(hostname)/$TIME/$FILENAME

It only takes 20 minutes to copy 180GB over the internet!
That is crazy fast.
In both cases you can play around with the number of threads for both pbzip2 and s3 multi part upload, the threads I use work for me but that depends on the size of your system.

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mysql multi threaded slaves (mts) slower than single threaded

I work @ weheartit.com where we rely on MySQL.
I’ve seen very little published about mts and nothing from outside a lab so I decided to test it out.
The results weren’t good.

Our main database group has 4 active schema, is running 5.6.12 and when a slave gets our of sync its takes a while to catch back up to the master.

One of the most interesting features for MySQL 5.6 is multi threaded slaves.

Without this feature the sync speed is limited to a single thread running on a single core.

Before I start let me clear up this point about mts which is that this feature will only help if you are running more than 1 schema per host as each thread can only process one schema at a time.

That being said I went and upgraded one of my slaves to 5.6.12, restored an xtrabackup to it.

Then I added the following lines to the my.cnf and ran start slave.


binlog-format=STATEMENT
 slave_parallel_workers = 4
 master_info_repository = TABLE
 relay_log_info_repository = TABLE

Now I can just run show slave status\G and watch it catching up.

However once it was caught up I stopped replication on the mts host and single thread slave for 20 minutes.
Then I started the slaves and it turns out that the single threaded slave caught up faster.
What?
to eliminate disk and RAID configs( they were the same as I could tell) this next time I only stopped the sql_thread for 20 minutes.
Same results, the slave running mts is actually slower.

Looks like there is reason when you search for this topic the only posts are from people using it in a lab is because although it appears to function it doesn’t delivery what ultimately need to which is faster replication syncs.

I’ll keep watching the mysql releases and hope this gets fixed soon.