Turck MMCache for PHP

It seems that recently the compression level was made a configurable setting and set to the lowest compression level by default.

Why was this done?

Since content caching is done once, it seems to me using the highest level of compression (9) would be better as it would ensure smallest page sizes and save on the amount of disk/memory needed to store it.

I agree, unless you have a website who gets hundreads or thousands page views per secs, where caching for even 1 second can help, those peoples may need to lower the compression level

But for in most case, level 9 work best
Btw, *IF* i remember correctly, MMCache have some short of caching feature via ETag: keep in mind that IE is unable to cache any gzipped content

Even in the instances when your server is sending A LOT of requests the benefit of compression (serving smaller file many time) far out weigh the extra 1/10th of a second that it would take to compress the content better.

The default compression level was previously hard coded to 7, the next release will have a configuration option to to allow you to alter this value but it will continue to default to 7.

After 7 the CPU Load to compression ratio is not as favorable so again the default compression level by default will remain unchanged but will be user configurable.

Wasn't it 6? ;)

It is possible it was set to 9, in any case when the next version of MMCache is released the compression level will default to the level of 2.4.6 and the configuration option will allow you to change it if desired.

Oh yes, it was indeed at 9
mod_gzip/PHP zlib have it at level 6 by default

Anyhow, since the compression is done once, wouldn't having level 9 best? (Even if the saving is minimal)