Limits
The most memory and processor time an app may use. Limits cost nothing by themselves: you pay for what the app really uses, and they change without a restart.
Updated 17 Oct 20263 min read
There are no plans or sizes on Tanzahost. Each app has two limits that you set: the most memory it may hold, and the most processor time it may use. Limits cost nothing by themselves. Your app pays only for the memory and processor time it really uses, measured every minute and charged every hour from your wallet. A limit is a ceiling that stops a runaway app from emptying your wallet.
Change an app's limits
Open the app's page. The Limits card shows what the app uses now against its limits, like "180 MB of 512 MB".
Choose Change limits.
Move the Memory limit and Processor limit sliders. The rates, an estimate for the month and the most a month could cost are shown as you move them.
Choose Save limits.
The new limits apply while the app keeps running: changing them never restarts it. A memory limit below what the app uses right now is refused.
The numbers today
| Limit | Memory | Processor |
|---|---|---|
| A new app starts with | 512 MB | Half a processor |
| The highest you can choose | 4 GB | 2 processors |
| Before your account's first top-up | Up to 512 MB | Up to half a processor |
We may change these; the sliders always show the range you can choose from. Until your first top-up, an account can also have at most 2 projects and 3 apps. Your first top-up raises these, and they lift step by step as you pay more.
What a limit does
Memory: the app's processes can't hold more than the limit. A process that tries is stopped and started again, and you're told "ran out of memory" under the bell, and by email if you choose so in your alerts. Raise the limit, or find what uses the memory.
Processor: the app can't use more processor time than the limit. When it wants more, it runs slower; it isn't stopped.
Half a processor means the app may use up to half of one processor's time.
What you pay
You pay for use, not for limits. Two apps with the same limits can cost very different amounts.
Asha's Laravel app webreading today's prices
The estimate in the dialog comes from the app's own use over its last 7 days, or, for a new app, from similar apps in its location. It's rounded up, so it never says less than it should. See How billing works.
Workers and tasks
A worker or a scheduled task uses the app's limits unless you give it limits of its own. Each process is limited and measured on its own, so a busy worker can't starve your web process.
Databases
A database of its own has its memory and processor limits too, set and paid for the same way.
Choosing your limits
Start with the defaults, and watch the app's Memory and CPU numbers for a few days. See Metrics and alerts.
Give memory room: a limit about twice the app's normal use leaves space for busy hours.
Keep a spending cap on your wallet, so even a mistake has a ceiling. See Spending cap.