Memcached Expires Setting Best Recommendation

Hello, and thanks to all who reply. I am seeking opinions on and those who wish to share there experience on what would you recommend as the best setting for memcache expires vs the size of your store.

I currently have nitropack as my caching extension. I have enabled on my server memcache. My current setting for when memcache expires in nitropack is 86400 seconds. I currently have about 60k product skus. I dedicated i believe 4gb to memcache. I am going to eventually expand my product line to 100k in products. I thought about changing the expires setting from 24 hours to 7 days. but I am not sure about this. I would appreciate and recommendations, examples, best practices... etc so i know what i should or shouldn't do and or what I can and can not do. And or what problems i may have by increasing to high or decreasing to low. Thanks again.

If you increase to 7 days, your customers will see 7 days old data. This might be ok depending on your store. If your items not changing that often, then 7 days may be ok, otherwise may not. In fact it is that simple. You know better than anyone else what is the cache expiration time that is suitable for your store. And to answer to your question, in my opinion the cache expiration is not related to the store size.

However, before caching everything it might be better to try to find out if any other improvement could speed up the site. 100k items are not that huge number. Not small but also not huge. For example, if you use the categories items counter (numbers in parentheses), then I suggest to think about removing them.

But I have the page cache setting set for 7 days already which is what i thought showed old stuff for 7 days... so my follow up question i guess would be more so what is memcache exactly for? Pricing and stock quantity or product counts in categories? More so, what data does memcache display for "x" amount of time set by the expires?

Yes, I guess that is the next question
Well, I have not worked th nitropack but I guess what is chached depends on nitropack settings. The memcache itself is just the caching engine, it will cache whatever you say it to cache. The same would happened if you wanted to use file cache for example.

NitroPack can cache the database queries in OpenCart known for their slow execution time. If Page Cache or Browser Cache are enabled, on some places the Database Cache will be superseded by the other caches.

Use this cache when you want to optimize some frequent, but expensive database queries. Hard-disk and memory storage options are available.

--Taken from with in Nitropak

So thats what they say they use memcache for.

I think you should ask directly the creators of nitropack what are the queries they cache with this extension. I can only guess, but cannot be sure. I guess the product counts in categories but cannot be sure if they cache the whole product listing and products information such as price, stock. This may be subject of the page cache.

The only I can say is that every store has its own requirements which means a store might be ok by caching everything for a month for example. Thats why extensions like nitropack usually have a lot of settings to give you the ability to make your own plan based on the specific store's needs.

So, I think asking the developers of the extension about the queries they cache, will help you make your own caching plan.