Oren Eini

aka Ayende Rahien

Oren Eini

CEO of RavenDB

a NoSQL Open Source Document Database

Get in touch with me:

oren@ravendb.net

+972 52-548-6969

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Comparison page for RavenDB and MongoDB

Oct 04 2009

What is happening with NH Prof?

time to read 2 min | 262 words

I was a bit quite on the NH Prof front lately, not because I didn’t work on it, but because I was fighting a really nasty bug. The way NH Prof is making use of WPF exposed a memory leak scenario inside WPF.

Luckily, once we were able to isolate the actual problem, it was relatively easy to find a workaround. If you care, the resolution was to keep a single instance bound to the view and replace its values, instead of providing a new instance when replacement was required. The problem is that this bug took forever to isolate.

Also included are a bunch of performance optimizations that I did along the way to resolve the OOM error. Those relate to better handling of batch statements, caching the result of SQL parsing and optimized NH Prof’s idle state (I’ll have a separate post about that).

In addition to that, I gave some additional love to DDL statements, making sure that NH Prof treated them specially and didn’t generate DML errors for DDL statements. Same goes for cached statements.

It is a bunch of small changes, the biggest of them was tracking down and viciously attacking the OOM error. For the next week, I am going to be busy at JAOO, but I also intend to spend some free time continuing the final polishing & touch ups.

The week after that, I intend to seriously start working on the 1.1 feature set.

Should be interesting.

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NH Prof

Comments

05 Oct 2009
12:57 PM

J

So, a quick question for you then. Are you sorry you went with a relatively new presentation framework, rather than classic WinForms? Do you feel the benefits of a completely new framework (with some subtle bugs) outweigh the potential risks? I only ask this, because I haven't dived (dove? diven?) into WPF yet, because its tough to get the motivation to throw out everything I've learned (again) about UI, and it seems like it's not quite fully baked. Thoughts?

05 Oct 2009
12:59 PM

Ayende Rahien

J,

I run into WinForms bugs as well in the past. You deal with those.

And yes, I think we did great there.

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FUTURE POSTS

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