mod_gzip is an external extension module for Apache, which uses Gzip compression method for a significant reduction of the volume of web page content served.

Disabling mod_gzip has advantages as well as disadvantages. Among the advantages are that you can save up some space in /tmp and the server load/resources used will be less when compared to the
scenario in which mod_gzip is enabled – because files will not have to be compressed before sending it to client. Also, mod_gzip is known to leave files in /tmp and other locations, which results in number of files being high in folders. At times, that results in thousands of files in /tmp which prevent new files being created. ie, it will cause a similar situation like /tmp being full – where OS cannot create new files in /tmp.

One of the disadvantages of disabling mod_gzip is that your server will consume more bandwidth. But this becomes a significant factor only when you have limits on the bandwidth usage.So choose for yourself considering the advantages and disadvantages of mod_gzip.