I am currently trying to modify a plugin for posting metrics to new-relic via AWS. I have successfully managed to make the plugin post metrics from swf to new relic (not originally in plugin), but have encountered a problem if the program runs for too long.
When the program runs for a bout 10 minutes I get the following error:
Error occurred in poll cycle: Rate exceeded
I believe this is coming from my polling swf for the workflow executions
domain.workflow_executions.each do |execution|
starttime = execution.started_at
endtime = execution.closed_at
isOpen = execution.open?
status = execution.status
if endtime != nil
running_workflow_runtime_total += (endtime - starttime)
number_of_completed_executions += 1
end
if status.to_s == "open"
openCount = openCount + 1
elsif status.to_s == "completed"
completedCount = completedCount + 1
elsif status.to_s == "failed"
failedCount = failedCount + 1
elsif status.to_s == "timed_out"
timed_outCount = timed_outCount + 1
end
end
This is called in a polling cycle every 60 seconds
Is there a way to set the polling rate? Or another way to get the workflow executions?
Thanks, here's a link to the ruby sdk for swf => link
The issue is likely that you are creating a large number of workflow executions and each iteration through the loop in workflow_executions is causing a lookup, which eventually is exceeding your rate limit.
This could also be getting a bit expensive, so be careful.
It's not clear what you're really trying to do, so I can't tell you how to fix it unless you post all your code (or the parts around calls to SWF).
You can see here:
https://github.com/aws/aws-sdk-ruby/blob/05d15cd1b6037e98f2db45f8c2597014ee376a59/lib/aws/simple_workflow/workflow_execution_collection.rb
That a call is made to SWF for each workflow in the collection.
Related
I am uploading a file via API for which I do a ‘polling’ and have the following 2 steps / transactions:
HTTP request to upload it for which I get a temporary status response ‘uploading’
While loop with a counter until the response status changes to ‘success’ but not more than 10 times.
${__javaScript("${STATUS}" != "success" && ${counter} < 10,)}
Question-1: How do I measure the response time for step-2 as it varies (sometimes, file will be uploaded in 2 times and sometime in 8 times)?
Question-2: How to make step-2 fail when the status has not changed to success even after all 10 iterations/ attempts?
Please could someone help?
Thanks,
N
Put everything under Transaction Controller, it will measure duration of all the iterations.
You can go for JSR223 Assertion, example code would be something like:
if (vars.get('counter') == '9' && vars.get('STATUS') != 'success') {
AssertionResult.setFailureMessage(true)
AssertionResult.setFailureMessage('Status is ' + vars.get('STATUS') + ' after ' + vars.get('counter') + ' iterations')
}
put it as a child of the 2nd request and if after 10 iterations the status won't be success it will mark the sampler as failed.
I use Github API V3 to get forks count for a repository, i use:
GET /repos/:owner/:repo/forks
The request bring me only 30 results even if a repository contain more, I googled a little and I found that due to the memory restrict the API return only 30 results per page, and if I want next results I have to specify the number of page.
Only me I don't need all this information, all I need is the number of forks.
Is there any way to get only the number of forks?
Because If I start to loop page per page my script risque to crash if a repository contain thousand results.
You can try and use a search query.
For instance, for my repo VonC/b2d, I would use:
https://api.github.com/search/repositories?q=user%3AVonC+repo%3Ab2d+b2d
The json answer gives me a "forks_count": 5
Here is one with more than 4000 forks (consider only the first result, meaning the one whose "full_name" is actually "strongloop/express")
https://api.github.com/search/repositories?q=user%3Astrongloop+repo%3Aexpress+express
"forks_count": 4114,
I had a job where I need to get all forks as git-remotes of a github project.
I wrote the simple python script https://gist.github.com/urpylka/9a404991b28aeff006a34fb64da12de4
At the base of the program is recursion function for getting forks of a fork. And I met same problem (GitHub API was returning me only 30 items).
I solved it with add increment of ?page=1 and add check for null response from server.
def get_fork(username, repo, forks, auth=None):
page = 1
while 1:
r = None
request = "https://api.github.com/repos/{}/{}/forks?page={}".format(username, repo, page)
if auth is None: r = requests.get(request)
else: r = requests.get(request, auth=(auth['login'], auth['secret']))
j = r.json()
r.close()
if 'message' in j:
print("username: {}, repo: {}".format(username, repo))
print(j['message'] + " " + j['documentation_url'])
if str(j['message']) == "Not Found": break
else: exit(1)
if len(j) == 0: break
else: page += 1
for item in j:
forks.append({'user': item['owner']['login'], 'repo': item['name']})
if auth is None:
get_fork(item['owner']['login'], item['name'], forks)
else:
get_fork(item['owner']['login'], item['name'], forks, auth)
I want to run two matlab scripts in parallel for a project and communicate between them. The purpose of this is to have one script do image analysis and sending the results to the other which will use it for more calculations (time consuming, but not related to the task of finding stuff in the images). Since both tasks are time consuming, and should preferably be done in real time, I believe that parallelization is necessary.
To get a feel for how this should be done I created a test script to find out how to communicate between the two scripts.
The first script takes a user input using the built in function input, and then using labSend sends it to the other, which recieves it, and prints it.
function [blarg] = inputStuff(blarg)
mpiInit(); %added because of error message, but do not work...
for i=1:2
labBarrier; % added because of error message
inp = input('Enter a number to write');
labSend(inp);
if (inp == 0)
break;
else
i = 1;
end
end
end
function [ blarg ] = testWrite( blarg )
mpiInit(); % added because of error message, but does not help
par = 0;
if ( blarg == 0)
par = 1;
end
for i = 1:10
if (par == 1)
labBarrier
delta = labReceive();
i = 1;
else
delta = input('Enter number to write');
end
if (delta == 0)
break;
end
s = strcat('This lab no', num2str(labindex), '. Delta is = ')
delta
end
end
%%This is the file test_parfor.m
funlist = {#inputStuff, #testWrite};
matlabpool(2);
mpiInit(); % added because of error message, but does not help
parfor i=1:2
funlist{i}(0);
end
matlabpool close;
Then, when the code is run, the following error message appears:
Starting matlabpool using the 'local' profile ... connected to 2 labs.
Error using parallel_function (line 589)
The MPI implementation has not yet been loaded. Please
call mpiInit.
Error stack:
testWrite.m at 11
Error in test_parfor (line 8)
parfor i=1:2
Calling the method mpiInit does not help... (Called as shown in the code above.)
And nowhere in the examples that mathworks have in the documentation, or on their website, show this error or what to do with it.
Any help is appreciated!
You would typically use constructs such as labSend, labRecieve and labBarrier within an spmd block, rather than a parfor block.
parfor is intended for implementing embarrassingly parallel algorithms, in other words algorithms that consist of multiple independent tasks that can be run in parallel, and do not require communication between tasks.
I'm stretching my knowledge here (perhaps someone more expert can correct me), but as I understand things, it does not set up an MPI ring for communication between workers, which is probably the explanation for the (rather uninformative) error message you're getting.
An spmd block enables communication between workers using labSend, labRecieve and labBarrier. There are quite a few examples of using them all in the documentation.
Sam is right that the MPI functionality is not enabled during parfor, only during spmd. You need to do something more like this:
spmd
funlist{labindex}(0);
end
(Sam is also quite right that the error message you saw is pretty unhelpful)
I have a method 'rate_limited_follow' that takes my Twitter useraccount and follows all the users in an array 'users'. Twitter's got strict rate limits, so the method deals with that contingency by sleeping for 15 minutes and then retrying again. (I didn't write this method, rather got it from the Twitter ruby gem api). You'll notice that it checks to see if the number of attempts are less than the MAX_ATTEMPTS.
My users array has about 400 users that I'm trying to follow. It's adding 15 users at a time (when the rate limits seems to kick in), then sleeping for 15 minutes. Since I set the MAX_ATTEMPTS constant to 3 (just to test it), I expected it to stop trying once it had added 45 users (3 times 15) but it's gone past that, continuing to add 15 users around every fifteen minutes, so it seems as if num_attempts is somehow remaining below 3, even though it's gone through this cycle more than 3 times. Is there something I don't understand about the code? Once 'sleep' is finished and it hits 'retry', where does it start again? Is there some reason num_attempts isn't incrementing?
Calling the method in the loop
>> users.each do |i|
?> rate_limited_follow(myuseraccount, i)
>> end
Method definition with constant
MAX_ATTEMPTS = 3
def rate_limited_follow (account, user)
num_attempts = 0
begin
num_attempts += 1
account.twitter.follow(user)
rescue Twitter::Error::TooManyRequests => error
if num_attempts <= MAX_ATTEMPTS
sleep(15*60) # minutes * 60 seconds
retry
else
raise
end
end
end
Each call to rate_limited_follow resets your number of attempts - or, to rephrase, you are keeping track of attempts per user rather than attempts over your entire array of users.
Hoist num_attempt's initialization out of rate_limited_follow, so that it isn't being reset by each call, and you'll have the behavior that you're looking for.
C# .NET 2.0 if that turns out to be applicable.
I'm going to start to get to the bottom of why a web service we have is acting slow - this web service jumps over a proxy, into another domain, queries a stored procedure for some data, and then returns a int/string/dataset, depending on what I asked for. I just wrote a console app that queries it repeatedly in the same fashion so that I can gather some statistics to start out with.
Keep-alive is turned off for each request, for some legacy reason nobody documented, so there's an immediate smell.
When looping through the same request multiple times, I noticed some strange behavior. Here's my output that reflects how long each iteration took to make the query and return data.
Beginning run #1...completed in 4859.3128 ms
Beginning run #2...completed in 3812.4512 ms
Beginning run #3...completed in 3828.076 ms
Beginning run #4...completed in 3828.076 ms
Beginning run #5...completed in 546.868 ms
Beginning run #6...completed in 3828.076 ms
Beginning run #7...completed in 546.868 ms
Beginning run #8...completed in 3828.076 ms
Beginning run #9...completed in 3828.076 ms
Beginning run #10...completed in 578.1176 ms
Beginning run #11...completed in 3796.8264 ms
Beginning run #12...completed in 3828.076 ms
Beginning run #13...completed in 3828.076 ms
Beginning run #14...completed in 3828.076 ms
Beginning run #15...completed in 3828.076 ms
Beginning run #16...completed in 3828.076 ms
Beginning run #17...completed in 546.868 ms
Beginning run #18...completed in 3828.076 ms
Beginning run #19...completed in 3828.076 ms
Beginning run #20...completed in 546.868 ms
Total time: 61165 ms
Average time per request: 3058 ms
I find it odd that there are multiple repeated values, down to a very small level. Is there some bottleneck that would cause it to be returned in the same amount of time repeatedly?
...hopefully my code for figuring out and displaying the millisecond duration isn't off, but the TimeSpan object tracking it is local to each loop, so I don't think it's that.
EDIT: Jon asked for the timing code, so here ya go (variable names changed to protect the proprietary, so might have fat-fingered something that would make this not compile)...
int totalRunTime = 0;
for (int i = 0; i < numberOfIterations; i++)
{
Console.Write("Beginning run #" + (i + 1).ToString() + "...");
DateTime start = DateTime.Now;
SimpleService ws = new SimpleService();
DataSet ds = ws.CallSomeMethod();
DateTime end = DateTime.Now;
TimeSpan runTime = end - start;
totalRunTime += (int)runTime.TotalMilliseconds;
Console.Write("completed in " + runTime.TotalMilliseconds.ToString() + " ms\n");
}
Console.WriteLine("Total time: " + totalRunTime.ToString() + " ms");
Console.WriteLine("Average time per request: " + (totalRunTime / numberOfIterations).ToString() + " ms\n");
The simplest way, without running a profiler etc, is to make the web app log the exact time (as near as you can get it, obviously) it starts the operation, various times within the call, and the time it finishes. Then you can see where it's taking the time. (Using a Stopwatch will give you more accuracy, but it'll be slightly harder to do.)
I agree that it's odd that you've got repeated times. Could you post the code that's measuring it? I wouldn't be hugely surprised to see some sort of captured variable problem which is confusing your timings.
EDIT: Your timing code looks okay. That's very strange. I suggest you record the times at the web service as well, and see whether it looks the same. It's almost as if there's something deliberately throttling it.
When you run it, does it look like it's taking the amount of time it says it is - i.e. when it says it's taken 3 seconds, is that about 3 seconds after the last line was written?
now you need to get some benchmark values for the other steps in the chain. See the server logs to get the time your request hit the webserver, and add some logging into the webservice code to see when the webserver hands off to the actual "working" code.
Once you've done that you can start to narrow down the performance of the slowest part, repeat as much as you like.
Could creating (and timing the creation) of the SimpleService be skewing your numbers?
What happens if you pull that out of the loop?
int totalRunTime = 0;
SimpleService ws = new SimpleService();
for (int i = 0; i < numberOfIterations; i++)
{
Console.Write("Beginning run #" + (i + 1).ToString() + "...");
DateTime start = DateTime.Now;
DataSet ds = ws.CallSomeMethod();
DateTime end = DateTime.Now;
TimeSpan runTime = end - start;
totalRunTime += (int)runTime.TotalMilliseconds;
Console.Write("completed in " + runTime.TotalMilliseconds.ToString() + " ms\n");
}
Console.WriteLine("Total time: " + totalRunTime.ToString() + " ms");
Console.WriteLine("Average time per request: " + (totalRunTime / numberOfIterations).ToString() + " ms\n");