Hi,
I have website with 20000 visitors/day and maximum is around 200 unique visitors online.
I have problem with syn_recv everyday in high traffic hours. It is stuck at 256 and slows down my website.
While my website is slowed, load is very low average 0.5 and RAM is normal around 600 MB.
Server characteristics
CPU: Intel® Core™ i7-4770
RAM: 32 GB DDR3 RAM
What can be a problem? Can i increase number of this connections above 256?
#sh /script/sysinfo
A. Kloxo-MR: 6.5.0.f-2014102601
B. OS: CentOS release 6.6 (Final) i686
C. Apps:
1. MySQL: mysql55-5.5.40-2.ius.el6.i686
2. PHP: php53u-5.3.29-1.ius.el6.i686
3. Httpd: httpd-2.2.29-1.mr.el6.i386
4. Lighttpd: --uninstalled--
5. Nginx: --uninstalled--
6. Qmail: qmail-toaster-1.03-1.3.45.mr.el6.i386
- with: courier-imap-toaster-4.1.2-1.3.18.mr.el6.i386
7. Dns: bind-9.9.5-1.el6.i686
D. Php-type (for Httpd/proxy): php-fpm_event
E. Memory:
total used free shared buffers cached
Mem: 15489 10947 4541 0 398 9882
-/+ buffers/cache: 666 14823
Swap: 16383 0 16383