Bridge Cache-fast, Lightroom Cache-Sloooooow

Bridge does NOT use the same thumbnail cache as Lightroom. If you open Bridge and go to Edit > Preferences > Cache you'll see where the Bridge cache is located. By default it is created on your installation drive but you can relocate it anywhere you choose.

Lightroom previews; both thumbnails and large previews, are saved in the Lightroom 3 Catalog Previews.lrdata folder that is created in the same folder with the LRCAT catalog. Those previews are distinct from the thumbnails generated by Bridge.

What is shared is the Adobe Camera Raw cache and that is different from either the Bridge thumbnails cache or the Lightroom previews cache. The Camera Raw cache is constrained by the amount of disk space assigned and only generates a dat file when the actual raw data is viewed. That means when you're looking at thumbnails in either Bridge or Lightroom, dat files are not created. Its only when you open a file in the Lightroom's Develop module or in ACR (running under Bridge) that dat files are generated. And since the ACR cache is limited by the amount of assigned disk space, the older dat files drop out when you open newer files.

At the end of the day its your choice but you're restricting your system performance by putting your cache on a Drobo. If you're so concerned about the small possibility of losing previews there are many better solutions from basic apps like SyncToy to more advanced backup applications.

Sorry.... I meant to say that I have both Bridge and Lightroom cache/Library on the Drobo so I do not understand why LR is painfully slow to load and Bridge, flies. Poor design or implementation in LR is my only conclusion.

There are enough people complaining about LR's performance that are not using external drives so I am not sure I would be happy with that solution. I can move the Library to an internal drive and see if that gives me what I want but I'd rather not have to do that. My original posting was to see if there was something I had not setup properly within LR.

btw. If you single click on a thumbnail in Library mode, it does generate a .dat file at that time.

bohdank wrote in post #11224153
I understand that it would be better to place the caches/libraries on the fastest access drive(s) I have BUT Bridge is also using the same cache and it loads virtually instantly. I would like to keep them on the Drobo for the redundency it offers, even though I am running RAID1 on my internal drives. I expect to be un-raiding my data disk after having bought the Drobo. I don;t want to be in a position to lose the caches due to a disk failure and then spending the better part of entire day rebuilding them.

I'll assume you have an adequate amount of RAM, since you seem to be well-equipped...

But, can you try out copying the catalog folder onto an internal drive and seeing how it works? I know nothing about Drobo drives, but if that's even a question, like PixelMagic is pointing out it could be worth making the change. If you copy the Catalog folder to the internal drive it includes the previews that the Library module uses. You can just use File/Open to browse to and open the .lrcat file. It will likely show missing files/folders, but you can right-click on a folder, preferably "high" in your Library folder structure, select Find missing files/folders, browse to the correct location, and LR is pretty good about following up a "find" with other re-connections.

If you do this and it improves the performance, then you have that data. If not, you can always just re-open the original catalog and nothing changes -- once you re-open the old catalog, you can delete the unwanted catalog and nothing is lost as long as you haven't imported anything new.

True... if it's just to see how it works I can copy the Library and point to it, within LR. If not much different, purge the library and change LR to point to the original catalog.

I have 8 gigs of memory.

bohdank wrote in post #11224375
True... if it's just to see how it works I can copy the Library and point to it, within LR. If not much different, purge the library and change LR to point to the original catalog.

I have 8 gigs of memory.

Right! Actually, to browse the Library module/previews, you don't even have to do the Find missing files/folders thing -- the Library works fine with offline images, but, well, whatever you want to try! And, yeah, 8Gb should be plenty! I run a 35-40K library off of 4Gb on a 32bit XP workstation!

Lightroom is based on an SQLite database and it isn't intended for use on networked drives since SQLite is a single user database schema. You can of course put your images on a networked drive but for optimal performance your catalog and preview files should be on an internal drive.

bohdank wrote in post #11224341
Sorry.... I meant to say that I have both Bridge and Lightroom cache/Library on the Drobo so I do not understand why LR is painfully slow to load and Bridge, flies. Poor design or implementation in LR is my only conclusion.

There are enough people complaining about LR's performance that are not using external drives so I am not sure I would be happy with that solution. I can move the Library to an internal drive and see if that gives me what I want but I'd rather not have to do that. My original posting was to see if there was something I had not setup properly within LR.

btw. If you single click on a thumbnail in Library mode, it does generate a .dat file at that time.

PixelMagic wrote in post #11224428
Lightroom is based on an SQLite database and it isn't intended for use on networked drives since SQLite is a single user database schema. You can of course put your images on a networked drive but for optimal performance your catalog and preview files should be on an internal drive.

The Drobo is not on a network. It's hooked up using ESATA.

bohdank wrote in post #11224517
The Drobo is not on a network. It's hooked up using ESATA.

So, from what I've heard, ESATA is a good connection, but I've heard iffy things about the Drobo -- I hope your test works!

I've heard the same thing also about the Drobo S but it isn't any slower (writing) than the ESATA docking station I have which is as dumb as a device can be so little overhead, there.

I haven't done any read comparisons.

bohdank wrote in post #11222813
Develop is actually fast rendering the first time.

As in: Before you start editing the images?

AFAIK, once you change a setting, the preview needs to be rendered anew. Maybe that causes the issue? (Not sure, just thinking out loud)

Victoria?

It's as fast as ACR is.... takes a second or 2 and you're done. The next time, because it now has a 1:1 of that image in it's cache, it comes up instantly.

Every time I have made a settings change I would force it to regenerate the thumbnails. None of the setting changes resulted in LR regenerating anything. All the important settings relating to Preview were already correctly set. The only thing I did along the way is increase the size of the cache and, lastly ran an Organize.

The performance is fine if a folder has, let's say, 10-50 or so images...it's that I have many that are > 300 and those are pathetically slow by any standards one wishes to use.

bohdank wrote in post #11224341
Sorry.... I meant to say that I have both Bridge and Lightroom cache/Library on the Drobo so I do not understand why LR is painfully slow to load and Bridge, flies. Poor design or implementation in LR is my only conclusion.

Drobo is usually significantly slower than internal drives. How's it connected?

I already told you one reason LR's slow, the files are too big, much bigger than bridge. Combine a slow drive with big files, it's slow.

tim wrote in post #11225276
Drobo is usually significantly slower than internal drives. How's it connected?

I already told you one reason LR's slow, the files are too big, much bigger than bridge. Combine a slow drive with big files, it's slow.

ESATA

The thumbnails on the Library page are not any bigger than the Bridge thumbnails, about 200k or less.

It's the Develop page (Lightroom Cache) that are big, 4meg each but that should only affect the Develop page.

Ah ok, this is just another Lightroom bug then.

Well, let us know when you get your catalog folder copied over and you can test it out on the internal drive!