Forum Discussion
Darren_Person_2
Nov 27, 2007Nimbostratus
Just as a follow up on this issue - we are still working through it with support, but here are the findings.
1. Multiple copies are present due to the combination of RAMCache and Gzip compression.
2. Apparently, compression happens before the caching of the object and uses the users browsers headers for ACCEPT_ENCODING. Since browsers implement this differently ie("deflate, gzip", "gzip, deflate", etc) - and the F5 stores each combination, we get tons of copies of the same object.
3. We created an iRule to try and minimize the number of potential copies, but it doesn't appear to be 100% working (hence, with the Development team).
Here is the example iRule that we tried:
when HTTP_REQUEST {
set var_accept_encoding [string tolower [HTTP::header "Accept-Encoding"]]
if {$var_accept_encoding contains "gzip"} {
CACHE::accept_encoding "gzipped"
}
else {
CACHE::accept_encoding "not-gzipped"
}
}
I'll keep you updated as we find out more from Dev.