Installing Lighttpd With PHP5 And MySQL Support On Ubuntu 10.10

MASTER=()
CURRENT=()
FIRST=1
for SERVER in ${SERVERS}; do
# collect all builds from server and populate CURRENT list
COMMAND=”${LS} -1fd ${WEBROOT}/${SITE}.*”
BUILDS=`${SSH} ${SSHOPTS} root@${SERVER} “${COMMAND}”`
for BUILD in ${BUILDS}; do
CURRENT=( ${CURRENT[@]-} ${BUILD} )
done

# if this is our first time around, copy CURRENT to MASTER
if [ ${FIRST} -eq 1 ]; then
MASTER=( ${CURRENT[@]} )
FIRST=0
fi

# now we do a compare between MASTER and CURRENT to see what builds
# are common
INTERSECT=()
for ENTRY in ${CURRENT[@]}; do
in_array “${ENTRY}” “${MASTER[@]}”
RET=$?
if [ "${RET}" -eq 0 ]; then
INTERSECT=( ${INTERSECT[@]-} ${ENTRY} )
fi
done
MASTER=( ${INTERSECT[@]} )

# clear the CURRENT array
CURRENT=()
done
Let me take a moment to explain the code above:

In order to check for array intersection, you need an in_array()
function

The first argument as the “needle” and the second is the
“haystack”
We verify that both parameters were passed
We simply loop through the haystack checking for the needle
If we find it, return success. Otherwise, eventually return
false

We need to loop through each server eventually, but we’ll start with
the first one

Run an SSH command to get a listing of builds
Populate an array ($CURRENT) with the builds that were found

Since the first server has no previous server to compare with, so we
just copy it to $MASTER

We then loop to the 2nd server, and put the result of getting builds
into $CURRENT

Now that we have the first server’s builds in $MASTER, we perform an
intersect with $CURRENT
We realize the need for an $INTERSECT array to hold the intersections
found above
$INTERSECT becomes $MASTER since it only contains similar builds from
the 1st and 2nd server

Looping to the 3rd server, we get the builds and put them in $CURRENT

Since $MASTER contains only the similar builds thus far, we again
compare it with $CURRENT
The intersect can now be used to compare against builds on the 4th
server, and so on

Once you finish looping through all servers, your $MASTER should
contain only similar builds

topics on running large numbers of machines
latest in large scale web infrastructure
latest going on in the IO space: (SSD, filesystems, SSD as L2 cache)
Applications of above technologies and what it means for application performance
Scalable and massive tcp daemons (i.e. Eric should come talk on scalestack)
exploration of pain points in current technologies and discussion on ways to fix them (from people really in the know)
A Hydra tutorial: starting with stock Ubuntu lucid, and exiting the tutorial with some analysis running on my project.
Something that completely takes me off guard and is awesome.

I’d love to see people from the MySQL, Drizzle and Rackspace worlds have a decent presence. For those who’ve never heard of/been to an LCA before: we reject at least another whole conference worth of papers. It’s the conference on the calendar that everything else moves around.

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