hi phillip,

On 4/20/07, Phillip Rhodes <[EMAIL PROTECTED]> wrote:
hi everyone,
Sorry for the basic question...

no problem and not a basic question at all ;-)


Because applications on multiple machines need to be able to grab jackrabbit stored 
content from the repository, I am using the SimpleDBPersistenceManager, with 
externalBLOBs set to false.  I realize that if I set externalBlobs to true, the blobs 
will be stored on the filesystem, but this makes the content "sticky", that is, 
accessible by only the machine that has it on the filesystem.

My question is:  Do I need to implement my own file caching for my application? 
 For example, if my application repeatedly retrieves a binary file from the 
jackrabbit repository, does jackrabbit cache the retrieved binary file on the 
filesystem for subsequent requests, or is each request cause the same blob to 
be read from the db?

it's the former. items read from the persistence layer are cached in
jackrabbit. this
includes binary properties (i.e. blob values). furthermore, blobs read
from a db are
internally spooled to a temp file. once the binary property associated
with that
blob/temp file is evicted from the cache, the temp file will be deleted.

therefore, repeatedly requesting the same binary property will in general not
cause the same blob to be read repeatedly from the db (assuming it is still
in the cache of course).

cheers
stefan


No problem either way, I just need to know, since I have 20,000 users with each 
user having their own collection of images on a very high traffic site.

Thank you everyone for all your help.  It's been great.

Phillip







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