[pve-devel] applied-series: [PATCH http-server v3 0/4] improve error handling in accept_connections

[Thomas Lamprecht]

On 10.12.20 15:02, Stoiko Ivanov wrote:
> v2->v3:
> * incorporated Thomas patient and excellent feedback (Thanks!!):
> * replaced the two error-flags by a single handle_creation flag,  based
>   on the observation that the code after AnyEvent::Handle->new() does not die
>   (and that we'd probably still shutdown the socket if it did)
> * replaced the calls to shutdown($fh, SHUT_RD) with calls to close - in case
>   accept() fails, we don't want to sent anything + it sents one tcp-packet less
>   (only rst+ack, instead of fin+ack,rst+ack)
> * replaced syslog+dprint by a single warn (in our AnyEvent daemons that results
>   in the line being printed to STDERR+to syslog with level warning)
> * squashed 1/5 (introduce dprint sub) and 5/5 (use it)
> 
> tested on my workstation (the cleanup by having an deny-acl in
> /etc/default/pveproxy and connecting 1000 times with openssl s_client)
> 
> original cover-letter for v2:
> v1->v2:
> * increment of connection count now happens right before the AnyEvent::Handle
>   is created
> * the handle-creation is guarded by an error-flag, and if it fails the
>   connection count is decremented (bounded to 0) again
> * as suggested by Thomas - added a debug print sub which includes the
>   package name, linenumber and function name where the printing happens
> * refactored all active debug-prints to use it.
> 
> original cover-letter for v1:
> This patchset is the result of investigating a report in our community forum:
> https://forum.proxmox.com/threads/pveproxy-eats-available-ram.79617/
> 
> The first patch fixes an issue where pveproxy worker processes would never
> exit (and eat quite a bit of ram+cpu) when 'getpeername' returned an error.
> 
> The second seemed to me like a sensible further cleanup, and the third patch
> will hopefully provide the needed information when debugging such things in
> the future.
> 
> Huge thanks to Dominik, who analyzed this issue with me!
> 
> 
> Stoiko Ivanov (4):
>   add debug print helper
>   accept-phase: fix conn_count "leak"
>   accept-phase: shutdown socket on early error
>   add debug log for problems during accept
> 
>  PVE/APIServer/AnyEvent.pm | 68 ++++++++++++++++++++++++++++++---------
>  1 file changed, 53 insertions(+), 15 deletions(-)
> 



applied series, much thanks!