# Worker process exited on signal 7 **URL:** \ **Category:** NGINX\ **Created:** [January 7, 2011, 10:41am UTC](https://www.ruby-forum.com/t/worker-process-exited-on-signal-7/201439 "2011-01-07T10:41:01Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![dubstep](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/d/cdc98d/32.png) [@dubstep](https://www.ruby-forum.com/u/dubstep)\ **Post date:** [January 7, 2011, 10:41am UTC](https://www.ruby-forum.com/t/worker-process-exited-on-signal-7/201439/1 "2011-01-07T10:41:01Z")
Hello everyone, I started to use nginx insted of lighttpd for a few days ago. It serves only static content (thumbnail pictures) and performs well, but yesterday it stopped working, and I got the following messages on the error.log. 2011/01/06 17:54:30 [alert] 7542#0: worker process 31959 exited on signal 7 I didn’t found anything about this error message on the net. The error logging level is “crit” because I don’t have enough storage to keep all the “file not found” errors 🙂 (The logging goes to a tmpfs partiton). So I restarted the lighttpd on that server, and it works now, so I didn’t think that it is a hardware error. Here is th the output of nginx -V: nginx version: nginx/0.8.54 built by gcc 4.3.3 (Ubuntu 4.3.3-5ubuntu4) TLS SNI support enabled configure arguments: --prefix=/opt/nginx –error-log-path=var/log/error.log --http-log-path=var/log/access.log –http-client-body-temp-path=/opt/nginx/var/cache/client\_body\_temp –http-proxy-temp-path=/opt/nginx/var/cache/proxy\_temp –http-fastcgi-temp-path=/opt/nginx/var/cache/fastcgi\_temp –without-http\_uwsgi\_module --without-http\_scgi\_module –with-http\_ssl\_module --with-openssl=…/openssl-0.9.8k –user=www-data --group=www-data --pid- path=/opt/nginx/var/run/nginx.pid –conf-path=/opt/nginx/etc/nginx.conf --with-http\_stub\_status\_module It is a x86\_64 system. At this machine the www data files are on two SSD-s, and one of those SSD-s are bad, bacause not all ‘secors’ (hey what is the correct term for sectors on SSD?) can be read. Can it cause this type of error? Thanks, Balazs – “Overhead, without any fuss, the stars were going out.” ---
**Author:** ![Balazs\_Pocze](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/e99b99/32.png) [@Balazs\_Pocze](https://www.ruby-forum.com/u/Balazs_Pocze)\ **Post date:** [January 7, 2011, 6:12pm UTC](https://www.ruby-forum.com/t/worker-process-exited-on-signal-7/201439/2 "2011-01-07T18:12:04Z")
Hello! On Fri, Jan 07, 2011 at 10:35:31AM +0100, Balazs Pocze wrote: > Hello everyone, > > I started to use nginx insted of lighttpd for a few days ago. It > serves only static content (thumbnail pictures) and performs well, but > yesterday it stopped working, and I got the following messages on the > error.log. > > 2011/01/06 17:54:30 [alert] 7542#0: worker process 31959 exited on signal 7 > > I didn’t found anything about this error message on the net. It looks like signal 7 on linux x86 is SIGBUS (oh, linux has architecture-dependant signal numbers… really intresting design decision). It usually generated on an attempt to access memory which doesn’t exists, and may be generated on various hardware problems as well. Under linux this includes uncorrectable memory errors as seen via MCA and problems reading pages after page fault (e.g. swap disk died, or mmap’ed file read failed). > The error > logging level is “crit” because I don’t have enough storage to keep > all the “file not found” errors 🙂 (The logging goes to a tmpfs > partiton). Just a side note: you may want to use “log\_not\_found off;” instead. > –http-proxy-temp-path=/opt/nginx/var/cache/proxy\_temp > SSD-s are bad, bacause not all ‘secors’ (hey what is the correct term > for sectors on SSD?) can be read. Can it cause this type of error? Obviously it can if you also have swap on these disks and/or read files via mmap(). While nginx doesn’t use mmap() to read files, something like may be used internally by OS for e.g. sendfile(), not sure. This may also be a problem in nginx which causes it to access nonexisting memory regions. To further debug the problem it should be helpful to obtain coredump and backtrace, as well as show full config. See [GitHub - nginxinc/nginx-wiki: ARCHIVED -- Source for the now archived NGINX Wiki section of https://www.nginx.com · GitHub](http://wiki.nginx.org/Debugging) for basic instructions. Maxim D. ---
**Author:** ![Balazs\_Pocze](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/e99b99/32.png) [@Balazs\_Pocze](https://www.ruby-forum.com/u/Balazs_Pocze)\ **Post date:** [January 10, 2011, 1:40pm UTC](https://www.ruby-forum.com/t/worker-process-exited-on-signal-7/201439/3 "2011-01-10T13:40:57Z")
2011/1/7 Maxim D. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid): > > > > Under linux this includes uncorrectable memory errors as seen via > MCA and problems reading pages after page fault (e.g. swap disk > died, or mmap’ed file read failed). Maybe yes. But I have no proof, and the problem is that: with lighttpd i don’t have this errors. So I don’t know what to think about it. > > The error > > logging level is “crit” because I don’t have enough storage to keep > > all the “file not found” errors 🙂 (The logging goes to a tmpfs > > partiton). > > Just a side note: you may want to use “log\_not\_found off;” instead. It is not a good sollution for me, because I need the 404 errors. (for fact, on this server I _only_ need the 404 errors to get (re)generated the thumbnail pictures, I don’t need these errors on error log, just in access.log (and a feature will be welcome, if I can direct the 404 logs into one log file, and 200’s to an another.) > > –http-proxy-temp-path=/opt/nginx/var/cache/proxy\_temp > > SSD-s are bad, bacause not all ‘secors’ (hey what is the correct term > > To further debug the problem it should be helpful to obtain > > coredump and backtrace, as well as show full config. See > > [GitHub - nginxinc/nginx-wiki: ARCHIVED -- Source for the now archived NGINX Wiki section of https://www.nginx.com · GitHub](http://wiki.nginx.org/Debugging) for basic instructions. there’s no swap space on this machine. – “Overhead, without any fuss, the stars were going out.” ---
**Author:** ![Balazs\_Pocze](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/e99b99/32.png) [@Balazs\_Pocze](https://www.ruby-forum.com/u/Balazs_Pocze)\ **Post date:** [January 10, 2011, 5:41pm UTC](https://www.ruby-forum.com/t/worker-process-exited-on-signal-7/201439/4 "2011-01-10T17:41:08Z")
2011/1/10 Maxim D. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid): > > > > > > > > > > architecture-dependant signal numbers… really intresting design > > This may be hardware-related error. No errors in lighttpd may > indicate it’s lucky (in case of memory errors) or using other > system interfaces (in case of paging-related problems). yeah, it can be. I’ll put an strace process to one of the workers, and look into the logs later. > > in access.log (and a feature will be welcome, if I can direct the 404 > > logs into one log file, and 200’s to an another.) > > “log\_not\_found off;” does exactly what you need - it just disables > logging “file not found” errors to error\_log. yep, I was wrong, you have right. thx. my bad. > > > > –http-proxy-temp-path=/opt/nginx/var/cache/proxy\_temp > > > > SSD-s are bad, bacause not all ‘secors’ (hey what is the correct term > > > > To further debug the problem it should be helpful to obtain > > > > coredump and backtrace, as well as show full config. See > > > > [GitHub - nginxinc/nginx-wiki: ARCHIVED -- Source for the now archived NGINX Wiki section of https://www.nginx.com · GitHub](http://wiki.nginx.org/Debugging) for basic instructions. > > > > there’s no swap space on this machine. > > It’s impossible to tell anything without further info. Please > follow provided instructions to obtain coredump. yep I’ll do that. thx. – “Overhead, without any fuss, the stars were going out.” ---
**Author:** ![Balazs\_Pocze](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/b/e99b99/32.png) [@Balazs\_Pocze](https://www.ruby-forum.com/u/Balazs_Pocze)\ **Post date:** [January 10, 2011, 5:19pm UTC](https://www.ruby-forum.com/t/worker-process-exited-on-signal-7/201439/5 "2011-01-10T17:19:46Z")
Hello! On Mon, Jan 10, 2011 at 01:38:53PM +0100, Balazs Pocze wrote: > > > error.log. > > > exists, and may be generated on various hardware problems as well. > > > Under linux this includes uncorrectable memory errors as seen via > > > MCA and problems reading pages after page fault (e.g. swap disk > > > died, or mmap’ed file read failed). > > Maybe yes. But I have no proof, and the problem is that: with lighttpd > i don’t have this errors. So I don’t know what to think about it. This may be hardware-related error. No errors in lighttpd may indicate it’s lucky (in case of memory errors) or using other system interfaces (in case of paging-related problems). > in access.log (and a feature will be welcome, if I can direct the 404 > logs into one log file, and 200’s to an another.) “log\_not\_found off;” does exactly what you need - it just disables logging “file not found” errors to error\_log. > > > –http-proxy-temp-path=/opt/nginx/var/cache/proxy\_temp > > > SSD-s are bad, bacause not all ‘secors’ (hey what is the correct term > > > To further debug the problem it should be helpful to obtain > > > coredump and backtrace, as well as show full config. See > > > [GitHub - nginxinc/nginx-wiki: ARCHIVED -- Source for the now archived NGINX Wiki section of https://www.nginx.com · GitHub](http://wiki.nginx.org/Debugging) for basic instructions. > > there’s no swap space on this machine. It’s impossible to tell anything without further info. Please follow provided instructions to obtain coredump. Maxim D.