Concurrent Rate Limit Policy for API Product ?

Google Cloud Apigee
1

Hi @Anil Sagar

Is the Concurrent Rate Limit Policy applied only at API Proxy level or also at API Product level like we have Quota Policy ?

Also suppose I have three API Proxies AP1, AP2, AP3 pointing to same backend having concurrent rate limit as 2,3,4 respectively then how it will behave ?

Does the total of 9 (2+3+4) concurrent hits are allowed for this backend coming from any of the AP1,AP2,AP3 ?

So will it start throwing error after 2nd concurrent hit to AP1 or after 10th concurrent hit to AP1 ?

2

@GAURAV , Find answers below,

Is the Concurrent Rate Limit Policy applied only at API Proxy level or also at API Product level like we have Quota Policy ?

  • It’s applied at API Proxy level. It doesn’t have any identifier element like in Quota to maintain separate counters.
  • But, You can have multiple Concurrent Rate Limit Policies which can be conditionally executed based on your requirement inside single proxy. It should work, never tried though.

Also suppose I have three API Proxies AP1, AP2, AP3 pointing to same backend having concurrent rate limit as 2,3,4 respectively then how it will behave?

  • It’s proxy specific since we have applied on the proxy level.
  • More than 2 concurrent connection on AP1 is rejected,
  • More than 3 concurrent connection on AP2 is rejected,
  • More than 4 concurrent connection on AP3 is rejected,

Does the total of 9 (2+3+4) concurrent hits are allowed for this backend coming from any of the AP1,AP2,AP3 ?

  • Again, It’s proxy specific. Yes, At a time, Target is allowed to receive a total of 9 concurrent connections.

So will it start throwing error after 2nd concurrent hit to AP1 or after 10th concurrent hit to AP1 ?

  • It will start throwing error after 2nd concurrent hit to AP1.

PS: Actual allowed numbers depends on number of message processors. Trial org by default has 2 message processors. For strict counters set distributed to true & check strict on ttl. For more details refer Policy Documentation .

Hope it helps.

3

Hi Anil,

In your reply you have mentioned that “Actual allowed numbers depends on number of message processors” . Can you please let me know the limit per message Processor and is there any property that needs to be set ?

Thanks,

Suma