In InnoDB there is an implementation of both mutexes
and RW-locks. The RW-locks implementation have been
improved by the Google SMP patches. Both of these
implementation relies on spin-loops as part of their
implementation. The defaults in InnoDB is to check
the condition, if it's not ok to enter to spin for
about 5 microseconds and then come back to check the
condition again.

If one reads the Intel manual how to do spin-loops
they propose to use a PAUSE instruction and then
check the condition again, so a much more active
checking of the condition. When we tried this out
using the sysbench benchmark we found that using
the Intel approach worsened performance. So instead
we tried an approach of putting the PAUSE instruction
into the InnoDB spinloop instead.

This approach turned out to be a success. Even on
machines with only one …

As a final followup to my MySQL 5.4 Scalability on 64-way CMT Servers blog, I'm posting MySQL 5.4 Sysbench results on a Sun Fire X4270 platform using the Intel x86 Nehalem chip (2 sockets/8 cores/16 threads). All CPUs were turned on during the runs. The my.cnf was the same as described in the previous blog.

The Sysbench version used was 0.4.12, and the read-only runs were invoked with the following command:

sysbench --max-time=300 --max-requests=0 --test=oltp --oltp-dist-type=special --oltp-table-size=10000000 \
   --oltp-read-only=on --num-threads=[NO_THREADS] run

The "oltp-read-only=on" parameter was omitted for the read-write tests. The my.cnf file listed in my previous blog was also used unchanged for these tests.

Here are the results graphically running on Linux.

The read-only results for MySQL 5.4 show a higher …

As a followup to my MySQL 5.4 Scalability on 64-way CMT Servers blog, I'm posting MySQL 5.4 Sysbench results on the same platform. The tests were carried out using the same basic approach (i.e. turning off entire cores at a time) - see my previous blog for more details.

The Sysbench version used was 0.4.8, and the read-only runs were invoked with the following command:

sysbench --max-time=300 --max-requests=0 --test=oltp --oltp-dist-type=special --oltp-table-size=10000000 \
   --oltp-read-only=on --num-threads=[NO_THREADS] run

The "oltp-read-only=on" parameter was omitted for the read-write tests. The my.cnf file listed in my previous blog was also used unchanged for these tests.

Here is the data presented graphically. Note that the number of vCPUs is the same as the number of active threads up to 64. Active threads beyond …

Today Sun Microsystems announced MySQL 5.4, a release that focuses on performance and scalability. For a long time it's been possible to escape the confines of a single system with MySQL, thanks to scale-out technologies like replication and sharding. But it ought to be possible to scale-up efficiently as well - to fully utilize the CPU resource on a server with a single instance.

MySQL 5.4 takes a stride in that direction. It features a number of performance and scalability fixes, including the justifiably-famous Google SMP patch along with a range of other fixes. And there's plenty more to come in future releases. For specifics about the MySQL 5.4 fixes, check out Mikael Ronstrom's blog.

So how well does MySQL 5.4 scale? To help answer the question I'm going to take a look at some performance data from one of Sun's CMT systems based on the UltraSPARC T2 chip. This …

As a final followup to my MySQL 5.4 Scalability on 64-way CMT Servers blog, I'm posting MySQL 5.4 Sysbench results on a Sun Fire X4270 platform using the Intel x86 Nehalem chip (2 sockets/8 cores/16 threads). All CPUs were turned on during the runs. The my.cnf was the same as described in the previous blog.

The Sysbench version used was 0.4.12, and the read-only runs were invoked with the following command:

sysbench --max-time=300 --max-requests=0 --test=oltp --oltp-dist-type=special --oltp-table-size=10000000 \\
   --oltp-read-only=on --num-threads=[NO_THREADS] run

The "oltp-read-only=on" parameter was omitted for the read-write tests. The my.cnf file listed in my previous blog was also used unchanged for these tests.

Here are the results graphically running on Linux.

The read-only results for MySQL 5.4 show a higher …

As a final followup to my MySQL 5.4 Scalability on 64-way CMT Servers blog, I'm posting MySQL 5.4 Sysbench results on a Sun Fire X4270 platform using the Intel x86 Nehalem chip (2 sockets/8 cores/16 threads). All CPUs were turned on during the runs. The my.cnf was the same as described in the previous blog.

The Sysbench version used was 0.4.12, and the read-only runs were invoked with the following command:

sysbench --max-time=300 --max-requests=0 --test=oltp --oltp-dist-type=special --oltp-table-size=10000000 \\
   --oltp-read-only=on --num-threads=[NO_THREADS] run

The "oltp-read-only=on" parameter was omitted for the read-write tests. The my.cnf file listed in my previous blog was also used unchanged for these tests.

Here are the results graphically running on Linux.

The read-only results for MySQL 5.4 show a higher …

As a followup to my MySQL 5.4 Scalability on 64-way CMT Servers blog, I'm posting MySQL 5.4 Sysbench results on the same platform. The tests were carried out using the same basic approach (i.e. turning off entire cores at a time) - see my previous blog for more details.

The Sysbench version used was 0.4.8, and the read-only runs were invoked with the following command:

sysbench --max-time=300 --max-requests=0 --test=oltp --oltp-dist-type=special --oltp-table-size=10000000 \\
   --oltp-read-only=on --num-threads=[NO_THREADS] run

The "oltp-read-only=on" parameter was omitted for the read-write tests. The my.cnf file listed in my previous blog was also used unchanged for these tests.

Here is the data presented graphically. Note that the number of vCPUs is the same as the number of active threads up to 64. Active threads beyond …

As a followup to my MySQL 5.4 Scalability on 64-way CMT Servers blog, I'm posting MySQL 5.4 Sysbench results on the same platform. The tests were carried out using the same basic approach (i.e. turning off entire cores at a time) - see my previous blog for more details.

The Sysbench version used was 0.4.8, and the read-only runs were invoked with the following command:

sysbench --max-time=300 --max-requests=0 --test=oltp --oltp-dist-type=special --oltp-table-size=10000000 \\
   --oltp-read-only=on --num-threads=[NO_THREADS] run

The "oltp-read-only=on" parameter was omitted for the read-write tests. The my.cnf file listed in my previous blog was also used unchanged for these tests.

Here is the data presented graphically. Note that the number of vCPUs is the same as the number of active threads up to 64. Active threads beyond …

Today Sun Microsystems announced MySQL 5.4, a release that focuses on performance and scalability. For a long time it's been possible to escape the confines of a single system with MySQL, thanks to scale-out technologies like replication and sharding. But it ought to be possible to scale-up efficiently as well - to fully utilize the CPU resource on a server with a single instance.

MySQL 5.4 takes a stride in that direction. It features a number of performance and scalability fixes, including the justifiably-famous Google SMP patch along with a range of other fixes. And there's plenty more to come in future releases. For specifics about the MySQL 5.4 fixes, check out Mikael Ronstrom's blog.

So how well does MySQL 5.4 scale? To help answer the question I'm going to take a look at some performance data from one of Sun's CMT systems based on the UltraSPARC T2 chip. This …

Today Sun Microsystems announced MySQL 5.4, a release that focuses on performance and scalability. For a long time it's been possible to escape the confines of a single system with MySQL, thanks to scale-out technologies like replication and sharding. But it ought to be possible to scale-up efficiently as well - to fully utilize the CPU resource on a server with a single instance.

MySQL 5.4 takes a stride in that direction. It features a number of performance and scalability fixes, including the justifiably-famous Google SMP patch along with a range of other fixes. And there's plenty more to come in future releases. For specifics about the MySQL 5.4 fixes, check out Mikael Ronstrom's blog.

So how well does MySQL 5.4 scale? To help answer the question I'm going to take a look at some performance data from one of Sun's CMT systems based on the UltraSPARC T2 chip. This …