intermittent issues with PA

I have been customer for a long time... Though, since 2 -3 weeks ago, I am really questioning the quality of service of PA... All our sites are rediculously slow and now we're in the middle of BIG release....ftp servers are not responding... we have been waiting for hours now and same problem. This is becoming really BAD for business now

@bemba and I are doing some work on this by email.

For anyone else that wants to investigate some performance issues, here's a few questions to think about:

  • are all the pages on your sites slow, or just some of them? if it's just some, what is the difference?

The speed of a web request can be broken up into several parts:

  • transit time, how long it takes the request to travel across the internet and back. You can investigate this in your browser's development tools. How does it compare with the actual time the server takes to process and respond?
  • database time: if your code does some database lookups, how much time do they take? How does that time change based on how many rows there are in your table (remember this can be a big difference between dev and prod). Have you got indexes on the right columns to keep queries fast?
  • (occasionally) any time spent reading and writing to disk -- do you need to read or write files? (other than the source code of the app)
  • finally, pure python processing time -- how much time does your code itself take? How long does it take to do any number-crunching or iterations? Do you have any sense of what its big-o complexity is?

One general tip is that the database is usually faster than python. So, if you have some functions that retrieve a lot of data from the database, and then loops through it looking for particular records -- have a think about whether there are any ways to change your queries, and get the database to do the hard work, instead of doing it in python.

Thanks for the reply, however, one would assume any decent software developer would perform these tests upfront (during design...) So, the short answer to your question is yes, WE have performed all these tests (including many more listed here). We've ported our system in other platforms and response time is 5x more.

Though, one thing we've notice, the slowness is more noticed only on sites that are password protected using the PA option offered in the Web tab. Slowness is Server related, not App related. This happens even on a single/simple html page. Server takes a long time before even sending request to the app.

As far as Big O... OH my... it's like asking a human if he knows how to walk.

@bemba -- don't take it the wrong way, those suggestions weren't aimed at you personally, I didn't mean to sound patronising. We have a lot of different types of programmers on here, many are hobbyists, and wouldn't have any idea what big-O notation is. It's good to hear that you do though!

Still, the breakdown in the numbers between transit time / database time / any filesystem read/write time / pure processing time would be helpful for analysing the performance problems you're talking about. Do feel free to send them through to me in our email conversation.