Default Limits

[scott]

Im curious to know what other cPanel CloudLinux administrators have set for their default limits.

The recommended default limits given at - http://docs.cloudlinux.com/index.html?limits.html - to me, seem to be very high. Im curious to know what the purpose of these high default limits are. If the default limits are set high enough such that all hosting accounts (or the vast, vast majority of them) all fit under limits, then what are the limits for? Wouldnt you be just as well off with a normal CentOS system?

Web hosting has fallen to absurdly low prices. To me, it would seem to make sense that these absurdly low priced hosting accounts would have very low limits - default limits. And a bump up in these limits would warrant a higher priced hosting plan. But instead it seems that even low priced budget hosts with CloudLinux limits are still offering higher limits, such as those recommended by CloudLinux for their cheapest plans. This begs the question, what is the point of CloudLinux then?

I do realize that CloudLinux offers CageFS and mod_lsapi, which may be CloudLinuxs two greatest selling points. And its not really CloudLinuxs fault regarding the limits, they allow each server administrator to set their own limits. It just seems that most of the people using CloudLinux arent taking advantage of how these limits can be more efficiently deployed.

[iseletsk]

Hi Scott,

Default limits are in no way were supposed to be low end limits. Most of our customers switched from CentOS to CloudLinux at some point of time -- and they would be very surprised (and unhappy) if most of their clients would get limited.
Default limits are there to improve server stability after you convert a generic server from CentOS to CloudLinux.
After that, hosts usually start to figure out how things work and adjust limits based on packages, etc.

[sqh]

Hi Igor. Im a different Scott.

I have often thought that CloudLinux could do a better job of helping hosts to understand the various limits. The documentation is very limited, and does not begin to assist hosting providers in determining the best settings. I understand that every situation is different (different hardware, different numbers of customers, different types of customers, different business goals). Still, there is a need for more information.

For example, setting the Disk IO setting. The documentation at http://docs.cloudlinux.com/index.html?io_limits.html is very limited (maybe 7 sentences). The documentation could mention how a webhost could determine an approximate "good" setting... perhaps one needs to test the maximum Disk I/O read/write rates first? It might mention that different limits might be applicable when using spinning drives, versus SSD. What is the relationship with the Disk I/O setting, versus IOPS? I think the docs should also mention what the default value is (in case you remove it from LVE Manager. Maybe there are other tips or tricks you can think of to help system administrators to figure out what the best settings are for their environments.

As you know, Bogdan did a webinar that covered some of this topic and it was good -- I learned quite a bit. Is this webinar available online? The other Scott might like to view it, and I would like to view it again.

Thanks!

- Scott

[bogdan.sh]

Scott Mutter, some questions was really covered by webinar about limits, the presentation itself and questions/answers could be found at our Academy page: https://<a href="https://cloudlinux....ux-academy</a>

I am always comparing setting limits as a balance game - how to provide reasonable limits for customers so their websites are fast but same time keep server stable. As you said web hosting has fallen to absurdly low prices, why someone should pay hoster if his website is slow (due to low LVE limits).

Scott Neader, When I was doing a webinar I did some researches about IO/IOPS so provided recommended values for hdd/ssd. But yes I agree our documentation needs to be rewritten and this will be done. Currently we are preparing Getting Started Guide then will take care about docs.

[scott]

Is stability really an issue with plain old CentOS? I manage several plain CentOS servers and I dont have any problems with stability of those servers. Perhaps Im just lucky. Are hosting companies even trying plain old CentOS? Or are they just automatically turning to CloudLinux, just because its what everyone else is doing? Im just having a hard time trying to justify the cost of CloudLinux.

Perhaps "default limits" is a bad choice of words. Default limits is what I characterize as limits that arent attached to a particular package. For the sake of convenience, lets say you have 3 packages: Low, Medium, and High. IDEALLY, all of your clients would be on one of these packages. High would have a high amount of limits, Medium a medium amount of limits, Low a low amount of limits. In this sense, Im referring to "default limits" as limits imposed on accounts that somehow dont get attached to a package. Typically this would probably be the Low package limits. The majority of your clients may be on the Medium or High package.

Perhaps other web hosting providers dont understand the usefulness of these limits. Perhaps I dont. But to me, if you arent utilizing varying degree of limits, then whats the point of CloudLinux?

Again, for convenience sake lets consider 3 packages priced: $1/mo, $5/mo, $10/mo. Why should the $1/mo hosting package have the same limits as the $10/mo hosting package? Why would anybody ever order the $10/mo package? Or the $5/mo package? Ideally, dont you want to drive clients to your median package? Utilizing limits can help you get there. Im all for offering cheap packages, but my idea is not to bend over backwards to deliver everything imaginable to clients on the cheap packages, thats why other priced packages exist.

But it seems, what you have - and this may be my own misunderstanding - web hosting providers that dont fully understand how to set limits, what they are for, so they just use the CloudLinuxs described default limits for their cheap plans, and nobody ever upgrades. Other sane web hosting providers cant implement sane limits because too many others go off and give everybody everything for $1/mo.

Are sane web hosting providers offering different levels of limits based on package price? Or are you just offering a one-size fits all model with your defined limits?

Web hosting prices have gotten absurdly low. I dont see it as being sustainable. And most web hosting providers probably dont care if its sustainable or not because they arent fully comitted to the industry. They are just as content to popup one day and popout another day. What CloudLinux offers with their limits would appear to be a great idea, it just doesnt seem to be utilized properly. If you are using a one-size fits all model for your limits, then whats the point of paying for CloudLinux? Is it just for CageFS and mod_lsapi?

[iseletsk]

Yes, stability is still #1 reason people choose CloudLinux. If you have low density - you might not have stability issues. Once you start adding more and more customers on the server -- you will have this issue. I haven heard of anyone with 300+ customers per server that hasn experienced stability issues.
Of course, if you have just a handful of servers, and they have ~100 customers, and those are 16+ core servers, you might not have those issues.

Now, why such limits for different sized packages -> no reason. They should be different.

[scott]

Our CentOS 6 servers average about 450 accounts per. I have no problems with stability. Most are quad-core Xeon processors.

[iseletsk]

I am not sure what to say. Either your customers are great/long time customers, and you have weeded out all the bad apples. Or you are proactive of tracking / getting them off your server. Or your customers dont see when their sites are slow / no monitoring / no one tracks performance. Or they dont tell you about it (they dont raise support ticket) Or your utilization is very low (<30-40%). Yet, I am still surprised that you dont experience an incident every 2-3 months or so where you would have to go into the server, track down someone whos site is misbehaving, and do something about it.

[scott]

I have a few bad apples from time to time, but they are quickly found and dealt with.

To me, this all just kind of begs the question, are web hosting providers just installing CloudLinux for their servers without even thinking of whether or not it is needed?

Do web hosting providers not know how to manage a server and expect simply installing CloudLinux and cPanel to do all of that for them?

Im just trying to get a better understanding of the cost/benefits of CloudLinux on all of our servers. We dont have that many servers, but more than a handful. Licensing each them for about $10/mo is a substantial hit to the bottom-line, and (other than CageFS and mod_lsapi) Im not sure how much benefit there is.

[sqh]

Scott Mutter, we have been providing Linux-based web hosting since 2003. I can say that switching to CloudLinux has been the 2nd best decision we have ever made (with switching to cPanel being the best decision). Especially as customers have turned to CMS systems like WordPress, Joomla, Drupal, etc., we were often having to deal with customers getting their sites beat up by bots, script kiddies, search engines (both good and bad ones), etc. Load would skyrocket, Apache would crash, bad things would happen. CloudLinux pretty much stops this from happening, keeping users in their own sandbox... if it gets beat up, then only their site crashes.

IN ADDITION... so many other extremely helpful products come with the CloudLinux license, such as CageFS, Litespeed PHP Handler (mod_lsapi), PHP Selector, MySQL Governor... these are all things they could probably charge separately for and wed pay for them. (dont do that, Igor!). We also utilize KernelCare (kernel updates without reboot) from CloudLinux, although that is an additional cost. Support from CloudLinux has been very, very good for us as well.

If you are happy with your hosting environment... then maybe just close this browser window and keep moving? As for us, we are thrilled with the CloudLinux product and have it installed on every shared hosting server now. YMMV.

- Scott

[iseletsk]

1. If $10/mo is a substantial hit to the bottom-line -- I am sorry, but you are doing something wrong.
2. Any time you deal with a bad apple: you loose time (hopefully it is worth more than $10/month), your customers are unhappy (slow server, etc).
3. You dont realize you see 1 out of 100 bad apples unless you have superb monitoring that checks site performance. Switching to CloudLinux often coincides with a decrease in churn -- customers will often not tell you that their site was slow, they will move on.

In the industry where the churn is one of the major growth stoppers, and where sites performance & uptime are two of the most critical upsell points (unlike disk space or the number of mailboxes) - it is a must.

And yes, hosts install CloudLinux and expect it to weed out (or shape/throttle the resource usage) of all the bad apples.

Plz, check this page: https://www.cloudlinux.com/all-produ...w/cloudlinuxos -- results you can expect section.
The numbers were taken from actual hosting companies. It was mostly larger hosting companies, as smaller companies rarely have good tracking to report the numbers.

[morten]

I haven read the whole thread yet but I wanted to give you some feedback on this question you got Scott Mutter.
I have been in the buisness for around 15 years and we started out with CentOS and that worked well many years.

But we often got issues with accounts using alot of resources and also got 2 servers hacked on those 15 years.
So LVE and CageFS is worth every penny in my mind :-)
And of course mod_lsapi is a great addition so far. Just waiting for CL to get new features like the "freeze" of the processes. Then mod_lsapi will rock the hosting industry :-D

We
e hosting in a small country and not worldwide yet, but I have set these limits on all packages:
CPU: 200%
vMEM: 5120
pMEM: 3072
EP: 20
nPROC: 1024
I/O limit: 3072 KB/s
I/O operation: 1024
Inodes soft/hard: 500000 / 900000

But Im currently checking some stats on all servers and will adjust these so we can get more people to upgrade to higher packages and get some more income :-)

[scott]

It wasnt really my intention to elicit a negative response in this thread. I was taught to do my own research and not just follow the consensus public opinion. I also dont write the checks for servers and service we use within our company. But I am asked to submit a cost/benefit analysis and because I think Im pretty good at doing the research and because I have a limited insight into the companys books, I am always looking for ways to squeeze out the most performance for the least amount of cost. Ive been managing Linux systems for 20 years, web hosting Linux servers for the past 17 years.

The CageFS system that CloudLinux provides is great. In terms of security, theres really nothing that comes close to this. mod_lsapi for PHP is also a plus. Im not disputing these two features. Im also not really disputing the limits feature of CloudLinux, Im just questioning whether it is properly utilized within the industry, which again isnt really a fault of CloudLinux.

In this day and age, when entry level hosting packages start out with 10GB of disk space (some are even higher, some are unlimited) and nobody uses any where near that amount of disk space, whats the incentive to have any larger hosting packages? Why would someone who is using 500MB of disk space upgrade to a 50GB disk space hosting package? Granted a lot of that is just the competitive nature of web hosting, but there are also several web hosting providers that are there one day and gone the next and dont care if their clients lose their website. (I can remember when entry level web hosting was 50MB of disk space).

My argument is that the metrics for measuring web hosting should change. And these CloudLinux limits are a good place to do that. Lower priced packages get lower limits and if they find themselves hitting memory or concurrent connection limits, then perhaps they need to upgrade to a package with higher limits. But instead, what you see the industry doing is setting level limits across the board, such that a low priced package gets the same limits as a higher priced package, or that low price packages get limits set high enough that there is no incentive to ever upgrade and you are destined to repeat the same history that has lead to absurdly large disk spaced entry-level hosting packages.

Perhaps setting across the board limits on a server prevents any one account fr om overloading a server. But I havent seen enough of that in my research to make it worth it. This has caused me to question whether anyone else has done any hard research on this or if everyone is just going with the flow of consensus public opinion. Maybe Ive just been lucky in this regard, but without a lot of concrete evidence it just makes it hard to recommend to the uppers that do write the checks. Maybe weve just been unlucky compared to other hosting providers in selling higher priced, non-entry-level hosting packages.

If you can monetize limits, then I can see wh ere they would be useful. But its really going to take a more industry-wide shift to do this, and I havent seen that.

So when it comes to looking at the benefits of CloudLinux, I come up with:

CageFS: major plus plus
mod_lsapi: plus
Limits: neutral

When I originally started this thread, my intention wasnt for it to be negative towards CloudLinux and what they offer. It was just meant to provoke some thoughts and insight into how some of the CloudLinux features are being used and if they could be better utilized.

[iseletsk]

Scott,

I think most people dont compete on quotas/limits anymore. Disk quota or CPU quota -- this is just not the reason most people buy one package or the other.
I would also presume that 70% of the customer base would have no idea how much disk space or CPU they need. That is why you dont see CPU limits that often as package differentiator.

On the other hand, there are quite a few companies who do just that -- and set up different CPU limits per package and offer different packages based on that. The market is huge, and there are many approaches.
Yet, differentiating on resources is no longer the main one.

[sqh]

Scott Mutter.... you DO realize that CloudLinux lets you set limits on a per-package basis, right? What you think we SHOULD be doing... we ARE doing.

- Scott