Newbie IO question

[zodiac9797]

Hi,
I just wondering about the IO limit per user. The docs and recommendations seem to me almost very low (2mb/s - 50mb/s).
We have a website which is about 5mb big, and expect about 1000 concurrent visits. Shouldnt we set the IO limit according to the math 5x1000= 5GB (or at least 1GB/s what our networkcard can serve)? Or do I mix it somehow up and the IO hasnt to be so big?
Thank you

[egrechishkina]

Hello Johannes,
Thank you for your question.
IO limit is not calculated like that, the best way to determine that would be your disks performance tests. 1Mb/s can really be a low limit, you can test with 4Mb/s which is the recommended limit for a high-end hosting account.
It is also needed to know that IO limit doesnt take into consideration any disk cache accesses. So, even if file is loaded from disk cache 1000 times – it will not be counted towards IO limits. You can read more about it here and here.

[admin]

Hello Kate,
thank you very much for your explanation and the links, I will try as suggested.
kind regards,
Johannes

[skhristich]

Hello Johannes,
Please let us know if you have any questions.
Thanks in advance!

[skhristich]

I have 300 accounts in the server with disk performance as follow
1st run: 333.79 MiB/s
2nd run: 320.43 MiB/s
3rd run: 396.73 MiB/s
average: 350.32 MiB/s

How to determine IO limit? Is it mean 350.32 MiB/s divided by 300 = 1.2 MiB/s ?

[egrechishkina]

Hello Susan,
1.2 MiB/s will be the ideal limit, but you should also understand that not all your users will be using the maximum of their IO limits all the time. So, you can freely set a higher value for your accounts that the middle value. For a Typical Hosting Account, you can set IO limit at 1,5-2MB/s, High-End Hosting Account can have 4MB/s IO limit.