Speed problem downloading large file

[user3]

Thanks for all your answer.

Surely, I have tested using other parameters already.

below result is using "-n" parameter.

## apache 2.2.0

./ab -n 100 -c 1000 http://test.server:80/index.html.1

Server Software: Apache/2.2.0
Server Hostname: test.server
Server Port: 80

Document Path: /index.html.1
Document Length: 300260 bytes

Concurrency Level: 1000
Time taken for tests: 0.951 seconds
Complete requests: 100
Failed requests: 0
Broken pipe errors: 0
Total transferred: 36151432 bytes
HTML transferred: 36121061 bytes
Requests per second: 105.15 [#/sec] (mean)
Time per request: 9510.00 [ms] (mean)
Time per request: 9.51 [ms] (mean, across all concurrent requests)
Transfer rate: 38014.12 [Kbytes/sec] received


## listespeed

./ab -n 100 -c 1000 http://test.server:80/index.html.1

Server Software: LiteSpeed
Server Hostname: test.server
Server Port: 8080

Document Path: /index.html.1
Document Length: 300260 bytes

Concurrency Level: 1000
Time taken for tests: 2.629 seconds
Complete requests: 100
Failed requests: 0
Broken pipe errors: 0
Total transferred: 39494972 bytes
HTML transferred: 39447612 bytes
Requests per second: 38.04 [#/sec] (mean)
Time per request: 26290.00 [ms] (mean)
Time per request: 26.29 [ms] (mean, across all concurrent requests)
Transfer rate: 15022.81 [Kbytes/sec] received


Local and remote result was same.


Thanks for your concerns...

[Xorlev]

"Your download speed for above packages is throttled to 160KB/s regardless of the number of connections."

I see now. Very neat. Sorry I misunderstood.

[mistwang]

You have set the concurrency level too high, should not over 300 for standard edition. And the concurrency level should always be lower than number of requests.

And you cn increase the "Max MMAP File Size" under the tuning tab higher than the size of the test file in order to get the best performance.

[mistwang]

Spent a little time to investigate this issue.

Found that it is true Apache can serve large static file a little faster (upto about 30%) than properly configured lsws std.

The reason is Apache uses sendfile() for static file, lsws std just use plain read() or MMAP() + writev(), which is not as efficient as sendfile(). That's the main factor for serving large static file.

For most user it is not a big concern unless you have a Gb connection serving pure static large files. However, our Enterprise edition is highly recommended for this kind of application, it definitely beats Apache on both pure serving speed and scalability.

[ts77]

but in the professional version one can enable sendfile too.
wouldn't that help in that case already?

[xing]

The sendfile setting within professional does not take effect. If you click on help witin the admin gui, it will detail that sendfile settings is only applied for enterprise licenses.

Please note this "bottleneck" witin std/pro version is only applicable in a bi-directional GigE setup where both the client and server on a GigE connection which is not often the case if at all, in most real world siutations.

On a 100mb/s pipe, you will hit the 9.9MB/s pipe limit before hitting any i/o limit and apache has no advantage what so ever. The same goes to a real-world scenario where you have a much less than GigE interconnect to the internet and your web clients are on a < 10mb/s pipe to the inernet.

[madmage]

I as well have this issue. If the sendfile issue is what is causing this to occur, it is a shame. I'll be forced to switch back to apache, since I just can't afford the price of the enterprise server and the pro does not enable sendfile either.

[mistwang]

sendfile support will be turned on in professional edition in 2.1.13.

[madmage]

im still confused how you can claim that the std edition is FASTER than apache when it hands-down is not.

I had to switch back to apache for our http traffic, but i left lsws in place for our ssl traffic and the difference is blatant.
if i wget a 521k file, im getting average thruput here of 314.77K/s with apache. using lsws for the same exact file it goes at 12.07K/s.

how exactly is that faster than apache?

[xing]

With or without sendfile() support in the Standard version of LSWS, your result appears to be out of wack. 12KB/s vs 314KB/s? Not saying your result is wrong, but there appears to be something broken with your configuration.

With that said, Standard Edition of LiteSpeed is not optimized for raw static output due to the advantage of lack of sendfile() support that is available in Enterprise edition. Again, sendfile()'s advantage is not 30X so we need more info to replicate your test result.

Despite all that, the LiteSpeed Standard Edition IS more scalable than Apache given load. Try to compare LiteSpeed, any edition, vs Apache under 200+ requests per second (mix dynamic content and static), and the difference in speed and latency is without questioned.

The bigger your website, server load, the greater the advantage is LiteSpeed vs Apache.

If you can provide us with more details of your configuration, we can try to see what went wrong with you. Due to possible sensitive info in your configuration, you can email the LiteSpeed xml config files plus Apache config file to bug@litespeedtech.com. Please note the Apache + LiteSpeed version and the size of the the static file from your test.