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Im using the memcached module on AWS Elasticache in my python Flask app (with Flask-Cache)

When i try to set a file that is less than 1MB i need to repeatedly access to the cache, i have no issues. But when the file size increases more than a MB (the file could be a text file/csv/xlsx etc), i get the following error

Error: error 37 from memcached_set: SUCCESS

Im guessing its because of the size limit on a memcached item which is capped at 1MB. How do i increase this item limit to say 5-6 MB in AWS Elasticache ?

Are there any issues in increasing this item size limit in memcached ?

Shankar ARUL
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1 Answers1

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This page lists the parameters that we can tinker with in memcached http://docs.aws.amazon.com/AmazonElastiCache/latest/UserGuide/CacheParameterGroups.Memcached.html

If you do not specify a parameter group for your Memcached cluster, then a default parameter group (default.memcached1.4) will be used. You cannot change the values of any parameters in the default parameter group; however, you can always create a custom parameter group and assign it to your cluster at any time.

Create a new Cache Parameter group either from the AWS Console or using the AWS CLI and set the max_item_size to the size that fits your needs. Reboot your cache cluster for this change to kickin.

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On your local testing machine, if you have memcache installed, then you can increase the object size by adding this line at /etc/memcached.conf

# Increase object size limit
-I 128M

Then reboot your memcache with sudo service memcached restart for the changes to settle in

Shankar ARUL
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    If there are any potential sideeffects/issues with increasing the memcached item size limit to an arbitrary large number, do let me know ? Thanks – Shankar ARUL Jul 22 '15 at 08:26