My presentation at LOSUG on tuesday went down like a house on fire - I think it would be safe to say that the phrase for the evening was ‘It’s a cache!’.
For that to make sense, you need to look at the slides, which are now available here.
Attendance was great, but it seems the last minute change of day meant that some people missed the session. We had 151 people register, and about 80 turned up on the night.
I spoke with Brian Aker last week about the issues I found with decrement and increment while working on my book "Developing Web Applications with Apache, MySQL, Memcached, and Perl". He suggested I make sure that I was using the latest libmemcached. I checked, and the version of libmemcached that is included with Memcached::libmemcached is 0.21 - this is the version of Memcached::libmemcached I obtained from using CPAN (perhaps CPAN needs a new bundle...). So, I obtained the most recent version of Memcached::libmemcached from the subversion repository at https://perl-libmemcached.googlecode.com/svn, and it includes the lastest libmemcached, version 0.25. To make a long story short, I re-wrote my test script to test each operation individualy and time that, as well as compare the times to Cache::Memcached. The numbers are great and are reason enough to use …
[Read more]This is a quick post to show how one can issue commands to telnet session from a shell script or command line with out going into interactive mode. I use this to get stats from our memcache servers or issue a flush_all via telnet from a script/cron.
So without further delay, following command will telnet to local memcached server on port 11211 and issue one of the memcached commands, stats
(sleep .5;echo stats) | telnet localhost 11211
You may have to play with the sleep timer to get it to work for
your environment but in our .5 was the sweet spot. Good luck and
let me know if you have another shell command. Obviously we can
do this from perl, php, python, etc but the beauty of this is
that you do not need any other dependencies plus its a very short
command. …
I'm busy working on my book, "Developing Web Applications with
Apache, MySQL, Memcached, and Perl", writing about how
Libmemcached (particularly the perl interface to libmemcached,
Cache::Memcached::libmemcached/Memcached::libmemcached) is
faster. And it is, except when I was writing a test script to
compare, I first used Daisuke Maki's script that comes with
Cache::Memcached::libmemcached, tools/benchmark.pl (which I
modified to only compare Cache::Memcached to
Cache::Memcached::libmemcached)
==== Benchmark "Simple get() (scalar)" ====
Rate perl_memcached libmemcached
perl_memcached 6784/s -- -78%
libmemcached 30488/s 349% --
==== Benchmark "Simple get_multi() (scalar)" ====
Rate perl_memcached libmemcached
perl_memcached 1806/s -- -84%
libmemcached 11494/s 537% --
==== Benchmark "Serialization with get()" ====
Rate perl_memcached libmemcached
perl_memcached 6402/s -- …
I have been using libumem and
LD_PRELOAD to track down memory allocation problems
in a lot of applications over the years, and I just love the
runtime linker on Solaris (AFAIK you will find some of the
features on Linux as well). The fact that I can load other
libraries that replace or add functionality of the program is
just great. If you haven't read it already I would encourage you
to read the man page for ld.so.1. If you are a developer
using Solaris and haven't used libumem to hunt down
memory bugs, you should read this blog by Adam Leventhal.
Last week I spent an evening …
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In the course of writing my book, I am in the midst of writing
about memcached and how it has been used to alleviate the load on
MySQL. I'd like to have a section in this chapter called
'Memcached Use Cases' and I was thinking of posting to my blog to
see if anyone has some use-cases of how memcached helped their
organization or application. Please, if anyone has any stories to
tell of how they had a high load on MySQL and in the course of
switching to using memcached for tables they were formerly
hitting often they solved this problem-- how memcached helped
reduce that load, even to what degree it reduced it. I can give
attribution to these stories as well.
Thanks for any stories in advance!
There are all sorts of different interfaces to memcached, but you don't need any of them to make requests from the command line, because its protocol is so simple. Try this, assuming it's running on the usual port on the local machine:
PLAIN TEXT CODE:
This Thursday, Martin "MC" Brown will explain how
to use memcached in MySQL deployments.
MC is the author of the memcached section of the MySQL Reference Manual, and does all other memcached documentation in the Sun Database Group, too.
This MySQL University session will start at 14:00 UTC / 8am CST
(Central) / 9am EST (Eastern) / 14:00 GMT / 15:00 CET / 17:00 MDT
(Moscow). The virtual meeting room will open 15 minutes before
the hour. Point your browser to this address.
Here's the updated MySQL University schedule for the rest of this …
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I just uploaded one of my chapters in my book "Developing Web
Applications using Perl, Memcached, MySQL and Apache" (Wiley).
This was the 50% point. Man, this is a ton of work. Writing a
book really takes up every second of your life, which is really
hard when there are other projects you maintain - namely
DBD::mysql, Memcached UDFs, FederatedX and my interest in helping
with Drizzle. I've tried as much as possible to use my projects
as material for the book making it possible to do two things at
once, as well as make it interesting to write.
It's harder to write on reference material and explaining basic
concepts than it is to write about code examples. The code
examples I really enjoy because they are first interesting, and
secondly there are some tricks and code functionality
(particularly with Perl, DBI, stored procedures, etc) that I have
never tried out before despite having been writing code for many
years, that this book has …
Greetings! I have released Version 0.7 of the Memcached Functions
for MySQL. This release mainly consists of modifications to the
autoconf/automake files that caused some users problems linking
to libmemcached, hence the UDFs failing. This should fix that
problem, although I would like to make the "fix" I made a better
fix.
BTW, did I mention how much autoconf/automake perplexes me and
drives me crazy at times?!
The release can be found at:
http://download.tangent.org/memcached_functions_mysql-0.7.tar.gz
As well as
http://patg.net/downloads/memcached_functions_mysql-0.7.tar.gz