random musings from a twisted mind
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JMX and firewalls… or how to hate RMI slightly less
Jul 7th
So at least with Java 1.6 the JVM can use SOCKS for proxying RMI requests, so to get the wonderful jvisualvm (think 1.5 visualGC) working use the following incantations.
This requires the initial RMI registry port is open to the client.
First the initial SSH to server enabling the SOCKS tunnel
$ ssh -D localhost:9696 servername
And now for jvisualvm
jvisualvm -J-Dnetbeans.system_socks_proxy=localhost:9696 -J-Djava.net.useSystemProxies=true
props to http://stackoverflow.com/questions/1609961/visualvm-over-ssh for the hints
disabling atime updates on macos X
Jan 18th
Create the following plist file somewhere useful, e.g. /Library/LaunchDaemons/com.local.noatime.plist
<?xml version=”1.0″ encoding=”UTF-8″?>
<!DOCTYPE plist PUBLIC “-//Apple//DTD PLIST 1.0//EN” “http://www.apple.com/DTDs/PropertyList-1.0.dtd”>
<plist version=”1.0″>
<dict>
<key>Label</key>
<string>com.my.noatime</string><key>ProgramArguments</key>
<array>
<string>mount</string>
<string>-vuwo</string>
<string>noatime</string>
<string>/</string>
</array>
<key>RunAtLoad</key>
<true/>
</dict>
</plist>
Then run the following to pick up the change, or indeed, reboot:
% sudo launchctl load /Library/LaunchDaemons/com.local.noatime.plist
And you should now see the root file system mounted with noatime option, which should improve longevity of SSD boot drives
# mount
/dev/disk0s2 on / (hfs, local, journaled, noatime)
Mac Pro memory layouts
Aug 9th
Found the following little diagram to show how to balance the memory layout on the mac pro
more zfs and mac os X
Jul 17th
Finally – fixed annoying missing partition label problem I’ve had. When the box is rebooted (thankfully not a frequent occurrence) it’d not mount the ZFS pool and complain that i’ve not labled the drives (which is sort of true 
. So break mirror, label and reattach.
zpool detach pool1 disk3s2
diskutil partitiondisk /dev/disk3 GPTFormat ZFS %noformat% 100%
zpool attach pool1 disk2s2 disk3s2
# diskutil partitiondisk /dev/disk2 GPTFormat ZFS %noformat% 100%
Started partitioning on disk disk2
Creating partition map
[ + 0%..10%..20%..30%..40%..50%..60%..70%..80%..90%..100% ]
Finished partitioning on disk disk2
/dev/disk2
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *1.4 Ti disk2
1: EFI 200.0 Mi disk2s1
2: ZFS 1.4 Ti disk2s2
binky:~ root# zpool attach pool1 disk3s2 disk2s2
sign FAIL
Mar 31st
Notice this in Cambridge today – looks like a wee fail to me (there was a few more than the two bikes in the picture along the wall outside the college)
“Please do not lean cycles against this wall”
playing with textmate
Mar 1st
OMG (and other leet things), textmate has built in just about everything, ok probably faster using a real web browser to post a blog, but I’ll have to see how useful the svn and SQL bundles are.