I am just looking for confirmation that I understand the lambda settings correctly.
The minimum concurrency setting is 10, My lambda function takes 3000 ms.
So does that mean the maximum number of times my function can be called a minute is...
60 seconds / 3 seconds = 20 calls
20 x 10 concurrent = 200 function calls per minute.
thanks
Related
I have a Lambda function that has 3 event triggers here are the Cron job for each:
Cron 1: cron(50/1 22 * * ? *)
Cron 2: cron(50/1 12 * * ? *)
Cron 3: cron(*/15 * * * ? *)
Now Cron 2 Timestamp logs reads as follows, which is ok. Notice that it starts 2-3 seconds into the intended trigger:
10
2021-07-10T05:59:03.867-07:00
11
2021-07-10T05:59:03.867-07:00
12
2021-07-10T05:59:02.314-07:00
START
13
2021-07-10T05:58:02.988-07:00
END
14
2021-07-10T05:58:02.988-07:00
15
2021-07-10T05:58:02.547-07:00
START
BUT Cron 1 & 3 starts over 30+ seconds into the intended trigger. I compared everything possible and there are no settings that are different (to my knowledge). Any idea why 2 of the 3 events have a delay but one doesn't? I understand a small 1-5 second delay by reading here https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html but somethings seems to be off.
2021-07-10T06:30:37.253-07:00
2
2021-07-10T06:30:37.253-07:00
3
2021-07-10T06:30:33.929-07:00
4
2021-07-10T06:15:36.931-07:00
5
2021-07-10T06:15:36.931-07:00
6
2021-07-10T06:15:33.881-07:00
7
2021-07-10T06:00:34.037-07:00
8
2021-07-10T06:00:34.037-07:00
9
2021-07-10T06:00:33.596-07:00
The precision of Event Bridge is one minute:
All scheduled events use UTC+0 time zone, and the minimum precision for a schedule is one minute. Your scheduled rule runs within that minute, but not on the precise 0th second.
So your delays are perfectly fine and within the 1 minute interval.
I have a dead-letter policy configured for my Google Pub/Sub subscription as:
...
dead_letter_policy {
dead_letter_topic = foobar
max_delivery_attempts = x
}
{
"minimumBackoff": y,
"maximumBackoff": z
}
...
Plugging in various values, i am not seeing the retries happen at times i would expect. E.g.
max_delivery_attempts: 5
minimumBackoff: 10 Seconds
maximumBackoff: 300 Seconds
Seconds between retries:
15
17
20
29
max_delivery_attempts: 30
minimumBackoff: 5 Seconds
maximumBackoff: 600 Seconds
Seconds between retries:
12
9
9
14
15
18
24
24
45
44
58
81
82
120
..., and so on.
From this testing, it seems u need a high max attempts value to get actual exponential back-off? For my first data set, i would have expected the time between my last 2 attempts would have been closer to 300. From my second data set, it seems this would only be the case if the max attempts is set to the max value of 100. Is this assumption correct?
(also, this is a pull subscription)
Thanks
Related answer: How does the exponential backoff configured in Google Pub/Sub's RetryPolicy work?
The exponential backoff based on minimum_backoff and maximum_backoff roughly follows the equation mentioned in the question above (with randomization factor). The relevant factor to your question are
Maximum backoff is not part of the calculation when deriving the backoff interval. Maximum backoff setting is used to ensure we do not back off more than configured, even if the backoff interval computation results in such an answer. The rate of growth in interval duration still increases with retry, as visible from your test.
The multiplication factor, responsible for the growth in backoff interval, is a system internal detail and clients should not be dependent on it.
If you want the maximum backoff to happen before the dead letter event occurs, I suggest starting with a higher minimum backoff configuration.
I have following test plan to test concurrent user load test of a website -
Configuration set as -
Target Concurrency = 10
Ramp up Time = 1
Ramp up step count = 1
Hold Target rate time = 6
So it's creating confusion, what I am expecting that it will send only 10 requests at a time in 1 second but the result is it sends first 10 request at a time in 1 second and continue sending requests till 60 seconds.
Why it is so?
Keep Hold Target Rate Time to 1 sec to match your expectations.
The graph should reflect the settings you made.
Note: In the graph you shared, it is clearly visible that you kept Hold Target Rate Time to 60 sec (reflected in the graph also) which resulted in 60 seconds execution after ramp-up time.
Reference:
Refer Concurrency ThreadGroup section in the link
as per requirements for simulating 10 requests at a time in 1 second
Target Concurrency = 10
Ramp up Time = 1
Ramp up step count = 1
Hold Target rate time = 1
Keep Hold Target rate time till you want to run to test.
e.g 1 sec for running test plan for 1 sec, 1 min to run test plan for 1 min.
I create a NamedWindow at time 'T', it fires every 5 minutes, assume Subscriber will cost 30 seconds to output all results, for example, T+5min, fire start, T + 5 min + 30 second fire finish. Here is the problem: when I destroy the statements at T + 5 min + 10 seconds, will the subscriber just output 10 seconds and the rest results of 20 seconds be destroyed? subscriber will be interrupted immediately at T + 5 min + 10 seconds?
Esper never uses Thread.interrupt on a subscriber or listener.
I work with SoapUI project and I have one question. In following example I've got 505 requests in 5 seconds with thread count =5. I would like to understand how count has been calculated in this example.
For example, if I want 1000 request in 1 minute what setting should I set in variance strategy?
Regards, Evgeniy
variance strategy as the name implies, it varies the number of threads overtime.Within the specified interval the threads will increase and decrease as per the variance value, thus simulating a realistic real time load on target web-service.
How variance is calculated : its not calculated using the mathematical variance formula. its just a multiplication. (if threads = 10 and variance = 0.5 then 10 * 0.5 = 5. The threads will be incremented and decremented by 5)
For example:
Threads = 20
variance = 0.8
Strategy = variance
interval = 60
limit = 60 seconds
the above will vary the thread by 16 (because 20 * 0.8 = 16), that is the thread count will increase to 36 and decrease to 4 and end with the original 20 within the 60 seconds.
if your requirement is to start with 500 threads and hit 1000 set your variance to 2 and so on.
refrence link:
chek the third bullet - simulating different type of load - soapUI site
Book for reference:
Web Service Testing with SoapUi by Charitha kankanamge