A MySQL Story

The Taso Dump

I’ve gotto go, my time has come. (maintenance window needed)
Could not get a lock. (table lock)
I needed a blocker to ensure a single thread. (–single-transaction)

Finally, got a lock. (–lock-tables)
Need to ensure no transactions lost.
Dump, Dump, Dump. (mysqldump)

I’m having flow problems.
Was the buffer to small? (key_buffer_size)
Was it the query cache? (query_cache)
My Dirty Pages may be too high? (innodb_max_dirty_pages_pct)
Or was it just Too Many Connections? (max_connections)
But it was just waiting on the flush (flush tables with read lock)

Time passes, Time Passes. No output yet.
Is it network saturation?
Is it IO bound?
Do I need a better flushing method (innodb_flush_method)
No, it was just the lag? (Seconds_behind_master)

Dump is complete (unlock tables)
Now it’s time to Purge (purge logs)

If there is an attempt to restore.
The backup would be empty.
Blackhole would be found as the cause.
In the end, all transactions lost!

If you weren’t at Friday dinner after MySQL Camp II you missed it.
It’s not meant to be MySQL grammar correct, it’s just some random words we were throwing around.

Tagged with: Databases MySQL MySQL Camp 2 - 2007

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