ok. So if i fetch these 6500 entities through a backend and set them to cache for 8 days, will there be durability for 8 days?
My app is low trafffic app and there might be time period when there is no traffic to site setting instances to 0 for that time period. Thanks Deepak On Mon, Nov 21, 2011 at 9:20 PM, Jeff Schnitzer <[email protected]> wrote: > Memcache doesn't work that way. You don't get any guaranteed quantity of > cache and it's not guaranteed to last for any specific length of time - > memcache is a shared resource and google allocates it according to their > own magic algorithms. > > Data falling out of the cache every 4-5 hours? That doesn't sound like a > problem to me. If you have cache data that needs predictable durability, > consider a backend. > > Jeff > > > On Mon, Nov 21, 2011 at 10:59 AM, Deepak Singh > <[email protected]>wrote: > >> My application while on loading makes a read operation around 6500 rows >> which is fixed for app. I have set memcache for this feature with cache >> expiration to 8 days. Bu i observe that cache usually fails 5 to 6 times in >> day, so in that case my app has datastore read of around 6500 rows. Thus my >> app heavily uses datastore read quota whic is very costly to me. >> >> I have been unable to make cache available for 8 days or even working >> properly. >> >> It would be great if you can let me know how to optmize this cache >> properly. >> >> Thanks >> Deepak >> >> >> On Mon, Nov 21, 2011 at 4:14 AM, Brandon Wirtz <[email protected]>wrote: >> >>> Memcache is just a cache. Your values have no guarantee of being there >>> even >>> 1micro second after you did the write. >>> >>> If you post your code we might be able to help, but I assure you Memcache >>> does work. >>> >>> My app does reads from the datastore or memcache for every request, >>> sometimes to for initialization of variables... like Who am I, Why am I >>> here, what configuration am I in. And then to serve the request... >>> >>> We use a combination of instance memory and memcache to not have to talk >>> to >>> the data store. Datastore reads are "slow" compared to Instance Memory >>> and >>> Memcache. >>> >>> Datastore Write Operations 0.24 Million Ops 0.19 >>> $1.00/ Million Ops $0.19 >>> Datastore Read Operations 0.02 Million Ops 0.00 >>> $0.70/ Million Ops $0.00 >>> >>> >>> I didn't count the "reads in my app" to the "writes" but I know I do >>> reads >>> for initialization every time, and reads for data every time. I only do >>> writes on some requests... So I am going to be conservative and say >>> that I >>> do 3x as many reads as writes in my code, but so far today I have hit the >>> Datastore with a write 10x as many times as I have a read. That works >>> out >>> to my local memory and memcache saving me 97% of the time. >>> >>> I don't have an easy way to tell you how much of the time that is >>> instance >>> memory and how many times it is memcache, but I assure you it works. >>> >>> >>> >>> -----Original Message----- >>> From: [email protected] >>> [mailto:[email protected]] On Behalf Of Jamil Rzayev >>> Sent: Sunday, November 20, 2011 1:48 PM >>> To: Google App Engine >>> Subject: [google-appengine] Memcache doesn't work >>> >>> Hi. >>> >>> I have to use memcache to store some values frequently accessible by >>> application I am working on. >>> The Google App Engine Memcache doesn't work as it apparently removes >>> values >>> after a couple of minutes I store it at memcache. >>> >>> I really need any idea and would highly appreciate for any comments. >>> I have already tried to ask here, but got response that I need to store >>> values as soon as I read them and didn't work. >>> >>> I am still losing my values... >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "Google App Engine" group. >>> To post to this group, send email to [email protected]. >>> To unsubscribe from this group, send email to >>> [email protected]. >>> For more options, visit this group at >>> http://groups.google.com/group/google-appengine?hl=en. >>> >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Google App Engine" group. >>> To post to this group, send email to [email protected]. >>> To unsubscribe from this group, send email to >>> [email protected]. >>> For more options, visit this group at >>> http://groups.google.com/group/google-appengine?hl=en. >>> >>> >> >> >> -- >> Deepak Singh >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Google App Engine" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]. >> For more options, visit this group at >> http://groups.google.com/group/google-appengine?hl=en. >> > > > > -- > I am the 20% > > -- > You received this message because you are subscribed to the Google Groups > "Google App Engine" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/google-appengine?hl=en. > -- Deepak Singh -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
