Maximum size of object that can be saved in memcached with memcache.py

Question

I need to return a rather big file (11MB) to the user. For certain reasons, I can't just provide a direct url to the file (http://www.sample.com/mybigfile.exe); instead it must be accessed through code.

Instead of having to read it from disk over and over, I thought of saving it in memcached (if this is not a good idea, let me know). Everything seems to work, fine (no errors), but when I try to retrieve the file from memcached I always get None, as if the file wasn't cached.

Is there a size limit to what can be saved?

Here's the code:

def download_demo():     """     Returns the demo file     """     KEY = "xyz"     TIME = 86400 #24 hours      buff = memc.get(KEY)     if not buff:          file = open(FILENAME, 'r')         buff = file.read()         memc.set(KEY, buff, TIME)      print "Content-Type:application/x-download\nContent-Disposition:attachment;filename=%s\nContent-Length:%s\n\n%s" %    (os.path.split(FILENAME)[-1], len(buff), buff) 

Answer 1

As of memcache 1.4.2, this is a user-configurable parameter: ReleaseNotes142 * memcached @ Github

Configurable maximum item size

Many people have asked for memcached to be able to store items larger than 1MB, while it's generally recommended that one not do this, it is now supported on the commandline.

A few enlightened folk have also asked for memcached to reduce the maximum item size. That is also an option.

The new -I parameter allows you to specify the maximum item size at runtime. It supports a unit postfix to allow for natural expression of item size.

Examples:

memcached -I 128k # Refuse items larger than 128k.  memcached -I 10m  # Allow objects up to 10MB