How to maximize Throughput and small static content traffic

[track1]

Hello,
I'm having some trouble serving large amounts of static content.

With some 200-300 requests per second, it works perfectly, instantly and Load response below 1.00

But with 400-500 requests per second, load remains low (<1.00), but response sometimes is fast, most of times is slow.

It seems that some value goes to limit and don't allow more connections temporarily until it is released.

Max Connections: 5,000 (10,000 2-Cpu) (with 500req/s, usage is about 500-1000)
Smart Keep-Alive: No (tested and works betters with No)

All other features are default.

 

[NiteWave]

the 1G NIC may reach its limit
check value of
lsws web admin -> Actions -> Real-Time Stats-> Http Out
when 400-500 requests/second

 

[track1]

The bottleneck is not there, all files are small (max. 25kb), with 400-500 req/s only:
Http Out2,800-3,000KB

 

[track1]

Currently, with only 200 req/s it works perfect:

 

[mistwang]

Please check "top" output see if I/O wait is going up when traffic is high, if I/O wait is higher, means the disk sub system cannot keep up.
usually, I/O wait higher than 10% will cause obvious slowing down.
Also, check "netstat -s" if packet drop/re-transmission is high, your network is the bottle neck.

 

[track1]

I/O wait is always 0,0% (fast 2 x SSD with RAID)
sysctl.conf is also optimized to increase network limits

I increased some values in: Static File Delivery Optimization
and seems to work better, not sure if it's correct

 

[NiteWave]

>But with 400-500 requests per second, load remains low (<1.00), but response sometimes is fast, most of times is slow.
how did you measure fast/slow, during benchmark (400-550 reqs/s) ?

how about "ab" benchmark ? for example,
#ab -k -n 100000 -c 500 http://127.0.0.1/small_file.png

can see how much the NIC throughput can be.
also you can wget a 500G big file etc to measure the NIC capacity.