Your own MySQL Database Server on an Android Tablet

Following Roel’s post, Percona Server on the Raspberry Pi: Your own MySQL Database Server , I thought what other crazy gadget can I run Percona Server on? And having an Asus Nexus 7 Android tablet I decided to give it a try.

Anything below contains a risk that you break your tablet if you do not know what you are doing, so be advised.

First, we need rooted tablet, most likely with custom ROM. I personally use SmoothROM which already comes with root and a proper kernel.

Next, we install Linux environment, I used Linux Deploy App to deploy Ubuntu 12.04 LTS. It does not remove current ROM and works pretty must as a regular Android App. The process is easy, but time consuming. It took about 30 mins to download and install all needed packages. When installation is done and Linux started we are able to SSH to the tablet and get familiar Linux shell.

From now it looks totally like a regular Linux installation, with a difference that this is an ARMv7 architecture, so we won’t be able to download regular 32 or 64bit binaries built for Intel architecture. And we do not have ARM binaries of Percona Server, so we will need to build from sources.

So we install build environment

apt-get install build-essential cmake libncurses5-dev bison libaio-dev

wget http://www.percona.com/redir/downloads/Percona-Server-5.5/Percona-Server-5.5.29-29.4/source/Percona-Server-5.5.29-rel29.4.tar.gz

unpack and build. Not, not so simple, unfortunately there is a bug Non-portable code in client plugin (fails on ARM) which will not allow to build from plain sources.
We need to apply a small patch to source, which is available here.

After that to build binaries:

cmake . -DCMAKE_BUILD_TYPE=RelWithDebInfo -DBUILD_CONFIG=mysql_release -DFEATURE_SET=community -DWITH_EMBEDDED_SERVER=OFF
make -j2
make install

and if everything goes as expect we will have binaries in /usr/local/mysql, which we start

mysql> show variables like 'version%';
+-------------------------+------------------------------+
| Variable_name           | Value                        |
+-------------------------+------------------------------+
| version                 | 5.5.29                       |
| version_compile_machine | armv7l                       |
| version_compile_os      | Linux                        |
+-------------------------+------------------------------+

And a quick useless CPU benchmark just to understand some level of performance of tablet CPUs:

Processor       : ARMv7 Processor rev 9 (v7l)
processor       : 0
BogoMIPS        : 1993.93

mysql> SELECT BENCHMARK(10000000,ENCODE('hello','goodbye'));
+-----------------------------------------------+
| BENCHMARK(10000000,ENCODE('hello','goodbye')) |
+-----------------------------------------------+
|                                             0 |
+-----------------------------------------------+
1 row in set (5.12 sec)

to compare with Cisco UCS server:

model name      : Intel(R) Xeon(R) CPU           X5670  @ 2.93GHz
bogomips        : 5851.73

mysql> SELECT BENCHMARK(10000000,ENCODE('hello','goodbye'));
+-----------------------------------------------+
| BENCHMARK(10000000,ENCODE('hello','goodbye')) |
+-----------------------------------------------+
|                                             0 |
+-----------------------------------------------+
1 row in set (1.46 sec)

The next steps is to combine two tablets and run Percona XtraDB Cluster, but there is another bug Can’t build galera on ARM architecture which should be fixed before.

Now I have a hard time thinking about a practical application of running database on a tablet, but it was more to check capabilities of mobile gadgets, which are quite impressive I may say.