So far I have been using Coppermine and Gallery, but ZenPhoto seem to be a lot more flexible, so I am really eyeing it for my gallery (a few thousand pics). My current concern is performance. On my server, whenever I post a new bunch of pictures and new public is flowing in, Gallery seems to be overloading mySQL (first) and then the rest of the server's resources. So I am looking at ZenPhoto to replace a resource hog.

While I understand that nobody did the benchmarking, say for a few thousand pics gallery and around 12,000 visitors per month - would a decent shared hosting account suffice or are we talking about VPS/dedicated server for this case? This should give me a rough idea as to how much a resource hog the ZenPhoto would be.

Also, if you have any relevant experience with ZenPhoto - please share!

There was a thread about that some time ago with some reporting using ZP with large amounts of images but I don't remember the link. Please try a forum search.

Meanwhile recommended reading:
http://www.zenphoto.org/2009/03/troubleshooting-zenphoto/#11
http://www.zenphoto.org/2009/03/troubleshooting-zenphoto/#22
http://www.zenphoto.org/2009/03/troubleshooting-zenphoto/#23

Did use a search, but haven't found anything that answers my question. However, the links you posted somewhat are Just as a comparison, Coppermine (and, I think, NextGen for WordPress) process images on upload. It takes up space, but is easier on the server resources. According to the second link you posted (if I got it all correctly) there is no preliminary processing, so any time the image accessed it is downscaled programmatically. Which means - ZenPhoto will consume more resources.

Right?

Not quite, images are processed only once if viewed the first time and then these processed images are cached. They will only be processed again if you change a setting. This counts for all image like thumbnails and sized images (the bigger ones). The full size image you upload is not touched, so you can change image sizes on your without reuploading. Also you can precache images, too.

Wow, haven't been so off the mark lately! Thanks a lot, this sounds much much better then I thought.

Just to add Zenphoto is file system based, no images itself are stored in the database, just the info.

Zenphoto is great. I have been using it since last 6 months or so. It is working great for my sizable gallery and traffic. The matter of fact, recently I have been testing it for 3500+ mp3 gallery+images.. and I am getting very positive results.
Very flexible + Great support. I sincerely thank zenphoto team to keep it open source.

@acrylan:
in my wildest dreams I could not imagine anyone doing that. Well, except for one really annoying DMS system (about 400TB of data) that holds medical data papers and I do work with every day. But thanks for pointing that out anyway, I appreciate it.

@sh123:
thanks for feedback, can you share what kind of hosting are you using?

I have business hosting plan with one of the Canadian hosting company. Not a dedicated server though, but its a good one. I hope this helps.