Web Panel RAM Usage Calculation


Has the RAM usage calculation changed on the 16th this month? The reason I ask is because it used to hover around 100MB, now it max out at 300MB or whatever size I set my RAM allocation at. It seems to take the cached memory in account as well, whereas it didn’t before.

Just curious, that’s all. I wonder if anyone else notice it also. I didn’t want to bother Support about something trivial like this.


The calculation hasn’t changed. The amount of information we’re collecting and displaying has, though.

There was a note about this change in our February newsletter.


I just looked through the February 2012 newsletter and didn’t find anything about this change. I didn’t find anything in the January 2012 newsletter either.

I too am surprised at the sudden increase in RAM my Web Panel graph is showing for both my VPS and my database server.


Whoops. Looks like that was initially slated for the newsletter, but didn’t end up making the cut!

Here’s the “deleted scene”:

[quote]VPS Usage Reports Just Got Real

DreamHost customers with Virtual Private Servers have long had access to
visual usage reports: pretty graphs on the DreamHost control panel that
indicate the memory and CPU usage of a VPS over time.

We had hoped that these graphs would let you make informed decisions
about just how much RAM to allocate (and thus pay for) when managing
your VPS service. Unfortunately these graphs were not as accurate as
they could have been.

Now they are!

We’ve just upgraded these VPS performance graphs to give you MORE
information to help you make even BETTER decisions about how best to
configure your DreamHost VPS service.

The amount of working memory and the amount of memory devoted to disk
caching are each now represented in these graphs, giving you a clearer
picture of what exactly is going on with your virtual machine.

If you’ve got VPS service on your account you can now view the new-and-
improved graphs from your web panel at:


If you’re not a VPS customer, why not upgrade and see what all the fuss
is about? You can deploy new Virtual Private Servers (specialized for
either general web service or optimized for MySQL performance) in a
matter of minutes at:


Better VPS reporting has been a much-requested feature and we’re happy
to bring it to you. Thanks for letting us give you aids - visually! [/quote]


This doesn’t seem like an honest way of displaying memory usage for the average user.

If someone’s VPS is set to 500MB of memory but the server really only needs 250MB to run it will use the unused RAM as cache making it look like the server is maxing out on memory usage. Then the unsuspecting user ups their memory slider. If they panic and slide it to 1,000MB and again the server really only needs 250MB it will again use remaining RAM as cache once again making the graph look like they’re using close to their limit. Rinse and repeat.

DreamHost used to not include swap in the memory total and did away with that as folks kept setting RAM too low just letting the hard drive handle the overage as swap memory. Yeah, I could understand how that needed to be clarified and DH made the changes to the graph and prices were also adjusted accordingly. I didn’t like it but it was something I could live with.

But now many users will panic and keep paying for more and more RAM even if they don’t need it. DreamHost VPS is sells itself as being a personal server for the non *nix-geek admin. Seems like a way to rake-in the money from unsuspecting users. And the omission of this change from the newsletter is troubling. This is NOT a minor omission from the newsletter, this affects all VPS users. Sure, I can SSH in and view actual memory usage along with how much of that is caching but how many VPS users will know how to do that?

DH needs to push out that missing information to VPS users via email and blog, you folks also need to make it clear about how the memory usage is divided with with cache. This stinks as this will not help users make better decisions for themselves. For DH maybe, but not for users.

I’m not a *nix expert but hey, if I was I’m not sure I would stay on DH.


We’ve just upgraded these VPS performance graphs to give you MORE
to help you make even BETTER decisions about how best to
configure your DreamHost VPS service.

The amount of working memory and the amount of memory devoted to disk
caching are each now represented in these graphs, giving you a clearer
picture of what exactly is going on with your virtual machine.[/quote]

Bolding mine.

It’s not more information, it’s different information, they are not each represented in the graph, there’s only one line for a total that includes both parts. There is no breakdown from which you can see both parts.

The result is a highly misleading view of how much memory a vps really needs.


It doesn’t really bother me. I never rely on the graph anyways. I did like how it was before though. The way it was shown gave me an idea when the site has heavy traffic. With cached memory taken into account, it’s just flatline all day every day. It doesn’t give me any information. Restarting the VPS only lowers the line for a very short while until memory get cached again.

Now that I think about that, maybe that’s why the portion did not make it to the newsletter. I bet the editor thought the wording was misleading enough they had to remove it from the final version that got sent out.

EDIT: I suppose I can still use the CPU line to determine when my site is busy or not. :slight_smile:


Oho — I think I see the issue. We’ve changed the data we’re collecting, but the new UI isn’t live yet, so the display is a little misleading. New, more useful graphs should show up tomorrowish.


Thanks Andrew, will check it out when live.


@andrewf Thanks for the update, that clears things up a lot.

The new graphs are up but I think the Memory numbers are off? The memory usage is showing me at about 500-600% higher than what I’m reading after logging in via terminal, reading my logs and using ‘top -c’ or ‘free -m’

Also my PS MySQL is showing consistent memory usage 200% more RAM than I actually have allocated for the database server (not actual memory used, just that much more than what I have the slider at).

I suggest the next time you folks roll-out a feature like this, warning us ahead of time would be best. I realize that pushing out the UI before the new data collection method isn’t possible but you folks should put something on the blog and point to it via the Status Page right now.

Okay, there IS a blog post up right now. But even in the screen snapshots of the blog post the Memory numbers look off by a factor of 5-6x.


Confirming what mediabaron says: the numbers are off, the total is higher than the memory my VPS has (by nearly a factor 2). I also don’t see any graph at this time.


No graph showing up? Shift-reload; clear your browser cache if that doesn’t do it.

We’re aware that the numbers aren’t adding up right — as Dallas has noted on the blog post, though, this only affects the display in the panel. We’re looking into the issue.


It’s working now. I see what you are trying to do and what is wrong with the data: “actual memory” currently includes the cache, it should not. When that’s corrected the graph will look good (and be correct) and the “tabular version” should then also be correct.[hr]
An example might help, for my VPS the panel shows:

Cache usage: 211 MB
Actual usage: 262 MB
Total usage: 473 MB

However I have 380 MB as reserved resources. What it should be (and is in line with what free shows me):

Cache usage: 211 MB
Actual usage: 51 MB
Total usage: 262 MB


The new graphs look good and match my own data, it is indeed an improvement on what we had before.