Experiences in CAD Management – System Performance
by Mark Stefanchuk, CADmanage.com
I was thinking about all of the things a CAD Manager does and decided to start a list. It was very long. At the highest level the list is typically support, training, and development – a very basic IT management framework. That is, get feedback from support and address systemic issues first with training and if necessary with development. Of course, the details of the day to day activities of a CAD Manager paint a much more complex picture. The CAD Manager doesn’t just have to know how to reset passwords. The CAD Manager also has to be able to peel back the layers of the CAD system one by one to separate the relevant from the irrelevant. CAD support might appear to be as simple as demonstrating feature function, but more often it requires traversing multiple integrated systems.
A few years back I had a situation where several users were seeing really poor performance, but only when working in a CAD drawing. Basic drawing commands – lines, circles, boxes and text were really slow. Everyone had the same software, the same computer, the same OS, but only a handful of users were seeing performance degradation. What gives?
In large corporations there are large IT teams and on occasion they can be a challenge to work with. Their requests can seem ridiculous at times, but usually these requests or “push-backs” are opportunities to eliminate a suspected root cause. In this case, our IT partners were skeptical and told us that we were imagining the performance issue. Ok. A simple timing script resolved that. I created a macro to place objects into a drawing. Pretty simple really – time stamp before and after and take the difference between the two. In VBA use the timer function. The output will be in seconds.
Dim t1 as Single, t2 as Single t1 = Timer() ‘ do lots of stuff ‘ ... t2 = Timer() Debug.Print Str(t2-t1)
Test some stuff, but be sure that your macro tests remote resources not just local desktop operations. Open a file, or place a block (or cell) that resides on a server. If you want to run a file open test, run it from a VBS.
' VBS - open and close a MicroStation Files dim t1, t2, msApp t1 = Timer() Set msApp = CreateObject("MicroStation.Application") msApp.visible = 1 msApp.mbeSendCommand ("rd=C:\tmp\test.dgn") msApp.quit t2=Timer() '--- CREATE AN OUTPUT FILE SO THAT WE KNOW IT IS EMPTY Set tfo = CreateObject("Scripting.FileSystemObject") Set tf = tfo.CreateTextFile("c:\tmp\tout.txt", True) tf.WriteLine(" TIME FOR FILE OPEN AND CLOSE: ") tf.WriteLine(t2-t1) tf.close
The test did the job. We were able to prove that performance was bad on these select machines. Still no root cause, but we proved the problem existed. The next “push-back” – well it must be the CAD software. Hmm. I thought I had done enough, but I went ahead and stepped through my checklist (working inside out) – drawings same problem with a new/different drawings so it can’t be drawing file specific, data connections not applicable, CAD application versions and settings are the same, CAD engine configurations the same. There weren’t any differences related to the CAD environment.
Volley back to IT. At this point I had the evidence to demonstrate that the problem wasn’t due to the CAD environment. This meant that our IT partners now had to take a closer look at the differences in the desktop programs and utilities that they managed. This included many things including network, terminal windows, OS system and patches. Network diagnostics checked out, OS system and patches ok, anti-virus software was the same, but… there was a difference. Turns out the AVS settings were not the same. On the computers with the problem the check box to scan remote computers was checked. Every time the CAD program grabbed a file or resource from the server it was being scanned.
A systematic analysis of each component of our design automation platform eventually found the root cause. And, in this case the resolution was relatively simple. That is, turn off remote detection. No need for redundant scans of internally managed servers.
About Mark Stefanchuk: Mark is a VP and senior consultant with CAD Management Resources, Inc. He divides his time between developing innovative custom software solutions and helping clients navigate complex design automation environments. If you would like to find out how he can assist you with your design technology he can be reached by contacting us at email@example.com.