Let say your VPS has 128MB of memory. My understanding would be that if you had, say, another 128MB of 'burstable' memory, that if another guest on the system wasn't using all it's memory, or if there was some spare on the system, then your VPS could use that.
But, how much memory does your VPS really think it has available? and what happens if the other VPS (or the system) decides it wants it memory back?
Does OpenVZ just start killing off your processes until it free's up enough memory?
When my OpenVZ VPS is running with lighttpd, RAM usage is very low, but when I switch to Apache, RAM usage goes all the way up to the max. I've had this happen to two VPSs already and can't figure out why this happens.
I also have two other VPSs, one Xen and one Virtuozzo and have no troubles with Apache.
Few months ago I bought new small VPS box (OpenVZ, 128 MB RAM) in order to place there a new monitoring node of my site monitoring system. Such small amount of RAM is a challenge for operating system optimisation techniques (OpenVZ doesn’t have “swap” as Xen does).
First of all I discovered that apache2-mpm-worker (Apache implementation that uses threads) consumes more memory (100MB) than the classic version that use separate processes (20MB). I had to switch to apache2-mpm-prefork version then.
Next unpleasant suprise: small Python app eats 100MB of virtual memory! I checked that virtual (not resident) memory is taken into account by VPS. I applied some tools to locate memory bottleneck, but without success. Next I added logs with current memory usage to track call that causes big memory consumption. I tracked the following line:
server = WSGIServer(app)
is guilty for high memory increase. After few minutes of googling I located problem: default stack size for a thread. Details:This line creates few threads to handle concurrent calls
Stack size is counted towards virtual memory
Default stack size is very high on Linux (8MB)
Every thread uses separate stack => multi threaded application will use at least number_of_threads * 8MB virtual memory!
First solution: use limits.conf file. I altered /etc/security/limits.conf file and changed default stack size. But I couldn’t make this change to alter Python scripts called from Apache (any suggestions why?).
Second (working) solution: lower default stack size using ulimit. For processes launched from Apache I altered /etc/init.d/apache2 script and added:
ulimit -s 256
Now every thread (in apache / Python application) will use only 128 kB of virtual memory (I lowered VSZ from 70 MB to 17 MB this way). Now I have additional space to enlarge MySQL buffers to make DB operations faster.
There’s even better place to inject ulimit system-wide: you can insert this call in:
/etc/init.d/rc
script. Then ulimit will be applied to all daemons (as Apache) and all login sessions. I reduced virtual memory usage by 50% this way.
Note: you may increase stack size on stack overflow errors. In my opinion 256 kb is safe option for most systems, you may increase if in doubt. Still memory savings are big.
We're in the process of setting up our new VPS Server, and we can create a VPS with 256MB memory and with 512MB memory fine, but when creating one with 1GB memory, we get the error:
Could Not Start Vps, Reason: Unable to fork: Cannot allocate memory: Not enough resources to start environment: Container start failed:
Even though the server has 4GB RAM and no other VPS's running. Any ideas? Thanks.
[Edit]We now seem to get the problem for all our VPS's. I think it may be something to do with the Server not unallocating the memory, as we've provisioned and de-provisioned quite a few Servers
Taken from /proc/user_beancounters on this vps. This vps is given 512RAM and burstable to 1GB ram deal. On my whm server information, it is showing me 200+RAM, burstable to 500-600RAM. Am i really given what i am offer?
I'm really confused about burstable billing. I'm hoping you guys can help me out.
I'm currently with Softlayer and I have two dedicated servers with 2TB of bandwidth a month. So far this has been fine for me.
I'm getting ready to move to a third server and therefore I'm looking at colo space. The problem is that they all seem to charge by the Mbps instead of by the overall bandwidth you use.
The bandwidth here in Austin is expensive (About $200+ per Mbps) and I have no idea how much I'd need.
Here's a sample of the last 7 days of traffic on one of my servers
Any idea how much bandwidth I'd need? Also, are these colos just screwing with me? Should I be able to find a plan that charges me by overall bandwidth instead of using bustable billing?
What is the difference between RAM and burstable RAM?
What even is RAM!
I ask because I upgraded my server (again) today. I went from 256 RAM, to 512, now to 1024 of RAM. Is 1 gig of RAM good?
Also, I want to know in general if I am getting a good deal here
I have a VPS now with these specs: Dedicated RAM: 1024 MB Burstable RAM: 4096 MB RAID 10 Disk Space: 100 GB FREE Backup Space: 100 GB Premium Bandwidth: 4000 GB Dedicated IP Address: 2 Monthly Price: $119.99
does that seem like a good deal to you?
I ask because I am new to all of this, and don't know if I am getting jipped.
Should a site on this server run fast, if it is a high traffic "tube" site?
I have confused in these notions a little bit - Guaranteed RAM and Burstable RAM. What is the difference between them? I have found that in the VPS hosting from ServerPoint.com.
if a provider provides me a 1Mbps AIMS dedicated line for my dedicated server, is it possible for him to make it burstable to 1.5Mbps? i thought when i get a dedicated line i would be able to get max 1Mbps only? How is it possible that it can be burstable? Does that mean its not dedicated, instead shared?
I currently have the SilverVS package from RoseHosting: [url]
With this specification, I also have DirectAdmin running and my website is www.christianforumsite.com (A forum)
So far, It's really good but there are some hourly lag times and two very very short downtimes in a few months time span. RH told me that my site had a high memory usage and that I might have to upgrade it.
So my questions are:
1. Could forums take a lot of memory and force the OS to kill some processes. In my case the forum is active but it not like huge community. Traffic report on alexa: [url]
It appears on top if you search for christian forum or christian forums, so the bots might be doing some damage too. Also I am using DirectAdmin with the lowest plan.
2. Could upgrading to the next VPS plan make the site noticeably faster and eliminate the lag times I've been experiencing?
3. What specifically (RAM guaranteed/burstable, discspace) should be high in case of a growing forum. Any other recommendation?
I wonder what does this mean. I no what a 100mbit connectivity is but what does it mean by burstable.
Does it mean that the downloading will start off really fast and then go down to my normal internet connection. What i mean is that if i download say from the microsoft.com, It will start at about 400kb/sec and then slowely progress to 260kb/sec.
With my server with in a datacenter, it starts from about 100kb/sec and then makes it way up to 260kb/sec. I am moving datacenter. So what does it mean by burstable.
I'm currently in the market for a new VPS that will be used for a single website. The client had it on a shared server, and ended up having it get suspended from too many httpd connections one day. Though the 2+ months it's been up, there haven't been any prior issues, so I think there was just something on that day that people found the website.
Anyway, according to WHM's bandwidth log, it hasn't used more then 46GB in a month, so I don't foresee this account needing to surpass 100GB of bandwidth.
The amount if disk space being used it currently at 1GB but up to 3-5GB would suffice.
I've tried out Direct Admin, but I'm much more knowledgable with WHM and cPanel that if at all possible, I'd want that on it. I'd prefer not to have to pay extra monthly for a license; I'd like for it to be included in the price.
I'm not looking for full management, but just basic management (and having support that actually reads your tickets as opposed to repeating the same bs every other ticket.. speaking from personal experience with another *cough* VPS host.)
I'm looking for the price range to be under $30 a month for the specs needed.
I realize cPanel needs a bit more memory, so.. hopefully this is justifiable: Requirements: OS - CentOS CP - cPanel+WHM RAM - 128-256MB dedicated, burstable to 512MB+ (though not a necessity) DISK - 3-5GB of disk space (obviously more would be fine if it's available within PR) Bandwidth - 100GB Price Range - $30 or less
I've already tried out Primary VPS, so I don't want to go there. Spry's VPS is unmanaged, and I don't want to configure the VPS myself at all (I'm lazy and I really suck at SSH commands.)
If any of you guys can offer some ideas of VPS hosts to look into, that would fit the prereqs I listed, I would be forever in your debt (or not) but I'd really appreciate it.
I just don't want to deal with Primary VPS anymore, and have been stumped as to what other VPS hosts to look into. Obviously I'm still going to search around here, but sometimes I like hearing personal recommendations...
6 ) beeing d*cks *Why This Review* Originally the intention was to forget as soon as possible about what happened in the past three months and to move on with our new isp. To our regret, Leaseweb has besides the overall lack of service in the past months found it neccessary to kill our network connection without notice a day prior to the ending of our contract. Eventhough the impact is minimal, this gesture speaks for itself. *Ordering a Server*
Having been a leaseweb customer directly and indirectly for several years in theyre budget segment we to be fairly honnest have rarely had any trouble ordering, nor have we had any trouble with the delivery of the purchased servers.
We experienced differently when ordering the following :
Dell Poweredge 1950 2x Quad Core Xeon L5320 16 GB DDR2 4 x 300GB SAS raid 1+0 IP KVM card 1 x 100Mbps Full-Duplex 10 Mbps (95%) bandwith SLA : Best Effort OS : Debian Ordered 09/30/2008 - payment sent immediatly
I have a VPS. And have had an issue both when it was 1Gig and now I recently downgraded it to 768m, because I am moving some sites to a dedicated.
However, the part I am having trouble grasping is that when I look at graphs from Munin, it will typically always show 200-400MB free memory (and free -m and top agrees with munin), but Munin shows 'committed' memory that is above the total Ram on the VPS and once the 'committed' ram exceeds the VPS limit, processes start failing.
So, why is 'committed' memory exceeding the RAM on my VPS, when Munin, free -m and top all show there is free memory available?
Code: root@server [~]# free -m total used free shared buffers cached Mem: 768 449 318 0 0 0 -/+ buffers/cache: 449 318 Swap: 0 0 0 Here's a graph that munin produces that shows the 'committed' memory exceeding the total memory. [url]
I just got a new server Dual E5520 with 6GB RAM, SAS 15k rpm raid10. It's running well. However, the memory usage is just around 2.5GB, even when I have more traffic. Here is the kernel info
Quote:
# uname -a Linux server2.[url]2.6.18-128.1.10.el5 #1 SMP Thu May 7 10:35:59 EDT 2009 x86_64 x86_64 x86_64 GNU/Linux
Any idea that we can put more content into memory?
Most VPS offerings have "burstable" memory allocations. I get how you can do this with most things -- letting a VPS access more CPU cycles can be done pretty easily, and a 10 Mbps line burstable to 100 Mbps makes sense.
But how does the guest OS handle all of a sudden having more memory? Since a lot of VPS guests run without modification, how does this work? Does the typical Linux system support dynamic changes in RAM? I can only imagine that dealing with "un-bursting" is even more complex: suppose I have 128MB, burst to 512, but then the host node tries to reclaim some of it. Is the system smart enough to seamlessly swap out to disk when RAM "disappears?" I'd fully expect a kernel panic when the system's RAM shrinks in size, particularly when the RAM was in use.
I'm curious about exactly how all of this is managed. Given that 95% of VPS hosts give a burstable range of RAM, what exactly manages this? Is the virtualization platform handling this and somehow "tricking" the kernel, or is the guest system able to deal with changing RAM allocations? And, if the latter, is this a standard feature of the Linux kernel, or are guest OS mods still necessary to deal with burstable RAM?
I have a 512mb DV server with Mediatemple, which I am running 24 (ish) domains off (most of them static websites) and a teamspeak server. I would say MAX theres 10 users online at a time)
Now, I know its running out of memory because i get frequent QoS Alerts in plesk (kmemsize is apparently the memory size):
Oct 01, 2009 11:52:57 AMBlack zonekmemsize
I have attached my results (when I did top).
My questions are:
1. Should I be expecting to be out of memory running what I am?
2. Is there a way to see the problem domains (memory wise)?
3. Are there any ways I can reduce the memory? (I have followed this already: [url]
4. Where is the memory usage coming from (I am finding it very hard to understand TOP)
We are looking for a VPS to house a scala framework running on a JVM, from what I can gleen Xen would be the best route for us or is it possible that openVZ with enough dedicated ram would suffice, does anyone have a view on this?
Just how it actually works? I have a pretty good knowledge about Xen and Linux KVM (somewhat about VMware as well). Prior to joining WHT, I rarely heard about Virtuozzo and OpenVZ.
I'm just interested in RAM usage actually. I also read on some threads that you can oversell storage and net bandwidth as well? That just seems a little weird to me. I also used a fairly good amount of Solaris Zones as well.
Example, if I have a 8GB box and I leave some, say 512MB, reserved for CT0. 8192-512=7680 (I know the ACTUAL RAM amount will NOT be 8192), that leaves 7680MB use for CTs. So technically in OpenVZ if you dice out dedicated 512MB VEs... you end up with 15 right?
So you are able to sell more than 15 VPSs on a 8GB server box? If also set all burstable RAM to 1GB for all VEs.
In Xen, when you set dedicated RAM it is taken away from dom0, period. That's all there is to it, no oversell (Xen 3.3+ you can use ballooning to overcommit RAM, I know). Within CT in VZ, user is able to check beancounters to see the guaranteed/burstable RAM. Technically you can't lie to the users.
I researched around... when oversell in VZ and the RAM gets maxed out... VZ will try to slow/stop/kill processes in order to keep the guests happy, to me that's just dangerous. Why needs to kill processes for RAM saturation?
Anyone can shed some lights for me? Or point me to an article(s). It can be technical, I should be able to grasp.
I am trying to create some vps using openvz but after creating the vps with the Centos basic template 304mb i can't ping the ip and i can't view the centos welcome page in my browser (using ip and not domain, so i don't need to change there anything yet) and the most important is that i can't connect to the vps using ssh
I aks for many good users about my problem but i don' found a solution yet.
I ask my DC about ip's and they told me that the ip's are routed in my server.
When you're creating VPS container, you can ssh with that IP and login with your username and password correct? But, what is the problem when I successfully created a VPS, and when trying ssh into it, I can't. Ok, here we go. I want to create a 2nd vps and will be using it as my DNS server. I enter a set of IPs into HyperVM's IPpool. First IP: x.x.x.178 Last IP: x.x.x.182 Resolv Entries (space Separated) : Gateway (IP): x.x.x.x.177 NetMask: 255.255.255.248
Then I created a vps resource plan. And then I created a VPS and it use the first IP from above. I want to connect to SSH and want to make it as my DNS server but seems the IP are not responding, it wasn't even live. So, what is the problem here? Where I did wrong? Just to let you know, I successfully created 1 VPS before that and it works without any hiccups. Got even whm/cpanel installed as well on it. The thing that I suspected is that my DC pulled the IPs off me and assigned them to other server. Waiting for their reply on this though.
