← Previous day | Today | Search | Index
All times shown according to UTC.
| Time | Nick | Message |
|---|---|---|
| 20:00 | thd | kados: are you present? |
| 20:02 | kados | thd: yep |
| 20:07 | thd | kados: the page generation time is a function of network speed. Why is that? |
| 20:08 | kados | e? |
| 20:09 | thd | kados: on my dial-up connection I have circa 54 seconds while less than 1 second locally |
| 20:11 | locally meaning either another local copy of the same script or a text based browser on the remote system | |
| 20:12 | kados: but should a page generation time not be how long it took the script to generate the code for the page irrespective of the data transmission time? | |
| 20:13 | kados: the value is generated from a simple difference taken in Unix epoch seconds between the start and end of the script | |
| 20:14 | chris | the script doesnt stop until its delivered its content |
| 20:14 | think of it this way | |
| 20:14 | does a script that prints to a file run faster than one that prints to a console | |
| 20:15 | the answer is usually yes | |
| 20:16 | its the way i/o works, you cant push out output faster than the device receiving can handle | |
| 20:17 | thd | chris: so any script that generates a web page waits constantly for a data receipt acknowledgement? |
| 20:17 | chris | the script itself doesnt, apache does |
| 20:18 | which in turn tells the script | |
| 20:18 | thd | chris: so Apache is executing the code for the application language? |
| 20:18 | chris | its just like writing to a disk |
| 20:18 | the i/o handler has to tell the program give me more datat | |
| 20:18 | -t | |
| 20:19 | thd | chris: I can see the similarity to writing to file but it was counter intuitive |
| 20:19 | chris | how? |
| 20:20 | thd | chris: I had simple expected the time it took to generate a page was a function of the time it took to execute the code for the page on the local system independent of where the data was being sent |
| 20:20 | chris | its just the same as running a file that writes to a file locally |
| 20:21 | vs the same script that writes to a file over a network | |
| 20:21 | thd: that depends entirely on how you write your script and wear you do the timing | |
| 20:22 | ie, if you generate all the data, then stop the timer, then print it | |
| 20:22 | it should be the same irrespective of where you are printing it to | |
| 20:22 | if you time the print .. then thats dependent entirely on where its printing to | |
| 20:22 | make sense? | |
| 20:22 | wear=where of course :) | |
| 20:23 | thd | chris:ok, that makes sense |
| 20:24 | chris: yet writing out data as it is generated is perhaps the most common behaviour for web applications | |
| 20:25 | chris | yep |
| 20:26 | thd | chris: however, if my connection is slow then I could have a timeout because I exceeded the maximum script wait time at some point |
| 20:26 | chris | yep, but that would probably happen either way |
| 20:26 | whether its all generated then printed, or printed as generated | |
| 20:27 | thd | chris:you mean Apache would time me out if I was receiving to slowly? |
| 20:27 | chris | eventually yes |
| 20:27 | actually ur browser probably would | |
| 20:27 | before apache did | |
| 20:28 | but apache does clean up unfinished scripts | |
| 20:28 | otherwise you end up with a dead apache pretty fast | |
| 20:32 | ok, i have to go do some grocery shopping, back in a bit | |
| 20:37 | thd | kados: are you still there? |
| 00:23 | chris: have you fetched your groceries? | |
| 00:24 | chris: I have another related question |
← Previous day | Today | Search | Index