How much AppEngine Instance hours should I expected?

Question

I have just developed a mobile apps which basically for users to upload, download photoes, add, update, search , delete, refresh transaction, and query report. Every action need submit request to Appengine Server.

I am using CloudEndpoint, oAuth2.0 and Objectify to implement this appengine. When I'm testing alone, The instance hours has used up 40% . How much billing for instance can I imagine if 100 people using this app? How does it calculate the instance hours? by request of submitting? or by time of instance working on multiple request??

is it worth?

If my target is more than 100 users to using my apps. Is it worth? Could you please share me what exactly I misunderstood about this instance. Thanks

it's really hard to measure, much easiest way is to run it for a few months and get an average. but as I know from my experience, based on several projects with similar technologies, 100 users a day is less $50/mo, most likely it fits free quota, but it really depends on app architecture — Igor Artamonov
@IgorArtamonov Can I say 100 users or 10k users make a request at the same time and all users get the result in 30 secs, the hours spending of instance has no much different right? — Oktaheta
@IgorArtamonov I see, as long the pricing is make sense. Just afraid the billing is getting higher unreasonable. Thanks for your Answer :) — Oktaheta
oh, by "few dozens maybe" I meant X times more. I don't thinks 1 instance can handle 100 request/sec, default instances is pretty limited, just 600Mhz/128Mb. So probably for 100req/sec you'll have 50+ instances, and for 10kreq/sec few thousands maybe. or better to upgrade to more powerful instance. as I said it all depends on your architecture, i'm just guessing right now. 10kreq/seq is really big number, it's like 170m uniq users a month. are you making a new Facebook? I believe you'll get a good discount for such a big project — Igor Artamonov
100req/s is more that 1.5 million uniq users a month, anyway. average app, with 5k daily users, it have about 4-5 instances in peak (like 1-2 peak hours in the middle of the day). and it costs < $50 a month — Igor Artamonov

Mo'in Creemers Mo'in Creemers · Accepted Answer · 2015-05-22T12:28:25

As others have commented, the question is very hard to answer. The easiest answer I can think of is by looking at the response header "X-AppEngine-Estimated-CPM-US-Dollars". You have to be a member of the Cloud Platform Project (see the Permissions page in Cloud Platform developers console) to see this header (you can check it in your browser). The header tells you what the cost of the request was in US Dollars multiplied by 1000.

But think of it as an indication. If your request spawns other processes such as tasks, those costs are not included in the number you see in that header.

The relationship between Frontend instance hours and the number of requests is not linear either. For one, you will be charged a number of minutes (not sure if it's 15 minutes) when the instance spins up. And there are other performance settings that determine how this works.

Your best bet is to run the app for a while against real users and find out what the costs were in a given month or so.

How much AppEngine Instance hours should I expected?

1 Answers