DMX Virtual Provisioning, like everything else has good + bad parts

I really like DMX VP (aka thin provisioning), it’s great in the automatic wide striping, overcommit, etc but at the same time there are a number of things you need to be aware of that will annoy you.   VP is great in that I don’t really need to think  (care) as much anymore, those iops are wonderfully spread across the backend… until I do and then ouch.

On the DMX you lose a resonable chunk of things you might be used to, optimizer is surely one of my old friends.  I’ve been strugglilng a bit with  performance, not because VP is slow but tracking things back to a source is such a massive pain in the ass.  WLA don’t seem to know much about VP, so you now have an added layer of abstraction you have to find.  SO if I’m beating a 48x of my SATA drives in a pool into submission at 100 wonderfully even spread iops per spindle… finding the guy who is doing it becomes a click nightmare.   I’ve got close to 1500 tdevs attatched to that pool and I’ve got to go look at every single one of them (or at least select all of them) and they don’t all have to be nice contiguous numbers, some tdevs might belong to another pool so you’ve got to exclude them.  Additionally there is no way to tell which one is nicely spread across all the drives in pool and which one has started doing random iops across concentrated to a subset of the pool… because someone had written out data when the pool was at 48 spindles rather than the 100+ it is now.   So you see a subset of disks get hot in a pool, so who’s doing it?  You have to map the 1500 tdev’s to the physicals and try to look for a peak/valley at the same time.   I’m pretty sure I’ve got a “fix” for the unbalance in the new microcode (unfortunately not the who part)… Read more

VMWare + Java + overcommitment= sad… + SSD = ?

We are doing a overall of our core customer systems… unfortunately the developers have no idea as to what they are actually going to need.  They have us configuring bunches and bunches of VM guests with 8GB of ram in them to run Java.  Our VMWare guys dutifully looked at vmware memory commit rates on the existing and a sample of the new guests and said oh yeah we’ve got lots of space and let them do it.  They deployed a whole bunch of them over a week and turned them all over to devel to use.  While that was obviously bad it wasn’t because they were being complete idiots, we already purchased enough to double our vmware farm but had not received licenses yet.  So they did a quick look around and VMWare hosts said they had active memory free, devel was wanting their new environment up before the new hardware was ready to try and get ahead of things and the perfect storm happened. Read more

Went to the Oracle/Sun “this is what we are are event”

And what I found was a big ball of crap.  I tried very hard to simply avoid the whole thing; but I was told by someone higher than me that “you ARE going”.. so a colleague and I drove to the Dearborn Hyatt with probably about 100-150 other people to get the usual song and dance.  Maybe I’m just a super savant (ha, not likely as I’d have won the lottery a long time a go), but I knew the pitch and lack of details/commitment ahead of time.  You get an exec in front of you in these things, they are just like a politician and will not commit to anything.   Read more

Am I a luddite…

I’m not talking in the skilled English clothing craftsman destroying of looms way, but in the everybody else has gadgets why don’t I?  When I mention to my colleague that I don’t really have personal gadgets (iPhone, kindle, etc); I get the oddest of looks and sometimes even a “how can you survive” response.  My wife will contend that I have way to many electronic stuff already scattered throughout the rooms in my house; but I never have had any of the “personal” ones.  I don’t have a personal smart-phone (got an old blackberry that’s work supplied), I’ve never even owned a MP3 player (this gets me the most *what??* responses), I was even pretty late to the whole digital camera movement. Read more

Management software how I hate thee!!!

Management software… it offers so much but fails me in the end; I think that the reason there is so much derision for the software is that we as admins can see how much it gives us.  It’s tantalizingly close to making our lives easier but the last bit are forever out of reach mocking us for having expectations of things working, actually making us angrier than having no software at all.

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Welcome to The Geeks blog

These opening blog messages are always painful… but thanks for coming to my world.  I’ve been working in the trenches for over a decade and hope to impart a little of my opinions and the painful learning experiences over the years. 

Posts will most likely be about what I’m dealing with that day… mainly storage, with a speckling of VMWare and Linux.