pwb history page zoom-out is very slow

[dd1]

This is a tracking page for the problem with agmini history page: https://daq16.triumf.ca/?cmd=History&group=PWB&panel=v_p2

The zoom-out function responds very slowly, after I reached the “1 month” time scale, the page is stuck in “updating data”.

I will add more information here as I debug this problem (not clear if it’s the web page, mhttpd or the reading of data from disk).

K.O.

[dd1]

see 100% cpu use in mhttpd, this looks to be a problem with the mongoose web server library. K.O.

[dd1]

mongoose is sending data in blocks of 1460 byte, no wonder mhttpd bogs down with 100% cpu usage. (mongoose networking is single-threaded). I tried changing this to 1460000 bytes, seems to work, zooming out history pages is fast again. K.O.

[dd1]

Fixed. https://bitbucket.org/tmidas/midas/commits/d1eced971c1810ee87e98816b030d931b9f34397 K.O.