Premature end of response header

[justme]

Hi,
I recently upgraded my server to Ubuntu 16.04LTS and switched php to fastcgi+fpm, being tired of compiling lsapi manually for each security release. Everything works but sometimes software using header() replies cause a premature end of response header / abort request..., code: 4 and I can't figure out why. How can I debug this? There's no php errors in logs anywhere.
thanks !
edit: Well, running the script manually shows that it returned no data at times... My bad, investigating it !
While I'm at it, why is Firefox unable to display svg logo on admin page ?

 

[NiteWave]

being tired of compiling lsapi manually for each security release.

you can install pre-build lsphp packages now, no need build yourself in most cases.
please refer
https://www.litespeedtech.com/support/wiki/doku.php/litespeed_wiki:php:apt

 

[mistwang]

Please turn on debug logging then reproduce the problem.