I am new to VTune and was playing around with it. One thing that I was not able to figure out was how do I get multiple samples of the events after every 20 seconds and save them in a text file.
For example, run an application using VTune and get back the general exploration results every 20 seconds for 2 minutes. Which means, I should have 6 samples of the events at the end.
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I have a fairly large tabular model and most days it only takes 8-10 minutes but every few days it will take 4-5 hours. Where would I even being to start troubleshooting this. I looked at the ETL logs but all it shows me is the step that asks the model to be processed.
Someone mentioned seeing if it was processing in parallel mode or sequential but I can't seem to find any setting for that in VS 2017 which is what I'm using.
I should also mention that I manually process it, it takes the normal amount of time (8-10 minutes). It's only when the ETL to process it executes that I sometimes see this long processing time.
I have a program that make many queries to Google Search Analytics server. My program does the queries one after the other sequentially, so each instant, only one query will be in process.
Google has advised about a throughput limit of 2000 queries per each 100 seconds at most so to configure my system to be the more efficient it could be I have two ideas on mind:
Known that 2000 queries per 100 seconds is one query per each 0.05 seconds, i have separated my queries by sleeping the process, but only if any query take less than 0.05 seconds, so the time the process will sleep in that case is the remaining time to complete the 0.05 second interval. If the query takes 0.05s or more I trigger the following without waiting.
The second idea is more easy to implement but I think it will be less efficient: i will trigger the queries taking note of the time when the process start so if i reach 2000 queries before 100 seconds, I will wait the remaining time sleeping.
So far I don't know how to measure which one is the best.
Which is your opinion about the two options? Any of them is better and why? Any additional option I haven't figured out? (specially if it's better than mine)
Actually what you need to consider is that its 2000 requests per 100 seconds. But you could do all 2000 requests in 10 seconds and still be on the good side of the quota.
I am curious as to why you are worried about it though. If you get one of the following errors
403 userRateLimitExceeded
403 rateLimitExceeded
429 RESOURCE_EXHAUSTED
Google just recommends that you implement Exponential backoff which consists of making your request getting the error sleeping for a bit and trying again. (do this up to eight times). Google will not penalize you for getting these errors they just ask that you wait a bit before trying again.
If you want to go crazy you can do something like what i did in my C# application I created a request queue that i use to track how much time has gone since i created the last 100 request. I call it Google APIs Flood Buster.
Basically i have a queue where i log each requests as i make it before i make a new request i check how long it has gone since i started. Yes this requires moving the items around the queue a bit. If there has gone more then 90 seconds then i sleep (100 - time since ) this has reduced my errors a great deal. Its not perfect but that's because google is not perfect with regard to tracking your quota. they are normally off by a little.
I am analyzing a web application and want to predict the maximum users that application can support. Now i have the below numbers out of my load test execution
1. Response Time
2. Throughput
3. CPU
I have the application use case SLA
Response Time - 4 Secs
CPU - 65%
When i execute load test of 10 concurrent users (without Think Time) for a particular use case the average response time reaches 3.5 Seconds and CPU touches 50%. Next I execute load test of 20 concurrent users and response time reaches 6 seconds and CPU 70% thus surpassing the SLA.
The application server configuration is 4 core 7 GB RAM.
Going by the data does this suggests that the web application can support only 10 user at a time? Is there any formula or procedure which can suggest what is the maximum users the application can support.
TIA
"Concurrent users" is not a meaningful measurement, unless you also model "think time" and a couple of other things.
Think about the case of people reading books on a Kindle. An average reader will turn the page every 60 seconds, sending a little ping to a central server. If the system can support 10,000 of those pings per second, how many "concurrent users" is that? About 10,000 * 60, or 600,000. Now imagine that people read faster, turning pages every 30 seconds. The same system will only be able to support half as many "concurrent users". Now imagine a game like Halo online. Each user will be emitting multiple transactions / requests per second. In other words, user behavior matters a lot, and you can't control it. You can only model it.
So, for your application, you have to make a reasonable guess at the "think time" between requests, and add that to your benchmark. Only then will you start to approach a reasonable simulation. Other things to think about are session time, variability, time of day, etc.
Chapter 4 of the "Mature Optimization Handbook" discusses a lot of these issues: http://carlos.bueno.org/optimization/mature-optimization.pdf
I am able to get Performance counters for every two seconds in Windows Server 2008 machine using Powershell script. But when i go to Task Manager and check for the CPU Usage, powershell.exe is taking 50% of CPU. So i am trying to get those Performance counters using other third party tools. I have searched and found this and this. Those two are need to refresh manually and not getting automatically for every two seconds. Can anyone Please suggest some tool which gives the Performance Counters for every two seconds and analyzes the Maximum, Average of those counters and stores the results in text/xls or any other format. Please help me.
I found some Performance tools from here, listed below:
Apache JMeter
NeoLoad
LoadRunner
LoadUI
WebLOAD
WAPT
Loadster
LoadImpact
Rational Performance Tester
Testing Anywhere
OpenSTA
QEngine (ManageEngine)
Loadstorm
CloudTest
Httperf.
There are a number of tools that do this -- Google for "server monitor". Off the top of my head:
PA Server Monitor
Tembria FrameFlow
ManageEngine
SolarWinds Orion
GFI Max Nagios
SiteScope. This tool leverages either the perfmon API or the SNMP interface to collect the stats without having to run an additional non-native app on the box. If you go the open source route then you might consider Hyperic. Hyperic does require an agent to be on the box.
In either case I would look to your sample window as part of the culprit for the high CPU and not powershell. The higher your sample rate the higher you will drive the CPU, independent of tool. You can see this yourself just by running perfmon. Use the same sets of stats and what what happens to the CPU as you adjust the sample rate from once every 30 seconds, to once in 20, then ten, 5 and finally 2 seconds as the interval. When engaged in performance testing we rarely go below ten seconds on a host as this will cause the sampling tool to distort the performance of the host. If we have a particularly long term test, say 24 hours, then adjusting the interval to once in 30 seconds will be enough to spot long term trends in resource utilization.
If you are looking to collect information over a long period of time, 12 hours to more, consider going to a longer term interval. If you are going for a short period of sampling, an hour for instance, you may want to run a couple of different periods of one hour at lesser and greater levels of sampling (2 seconds vs 10 seconds) to ensure that the shorter sample interval is generating additional value for the additional overhead to the system.
To repeat, tools just to collect OS stats:
Commercial: SiteScope (Agentless). Leverages native interfaces
Open Source: Hyperic (Agent)
Native: Perfmon. Can dump data to a file for further analysis
This should be possible without third party tools. You should be able to collect the data using Windows Performance Monitor (see Creating Data Collector Sets) and then translate that data to a custom format using Tracerpt.
If you are still looking for other tools, I have compiled a list of windows server performance monitoring tools that also includes third party solutions.
The program in windows form application is working well until i use timer control where i choose the interval of it (1 ms) to get 1000 values, visually i should get these 1000 values in a period of one second but i get them in a period of about 14 seconds it's very slow.
Does anyone know why and how to solve this?