As title...

Last here I bought a Linode 512 and now I bought another Linode 512.

It's great to see that my new Linode 512 got a new CPU.

The old linode uses an Intel Xeon L5420, 4 core 4 threads using the old LGA771.

The new linode uses an Intel Xeon L5520, 4 core 8 threads using the newer LGA1366.

They bench quite similar due to the different frequency and cache but the new linode benches somewhat better.

The other hardware difference I can see is the difference in RAM.

My old one says:
cat /proc/meminfo
MemTotal: 504916 kB

My new one says:
cat /proc/meminfo
MemTotal: 435132 kB

dmesg | grep Memory (on old linode)
Memory: 503616k/524288k available (5818k kernel code, 388k absent, 20284k reserved, 2951k data, 520k init)

dmesg | grep Memory (on new linode)
Memory: 433024k/4202496k available (6041k kernel code, 3670464k absent, 99008k reserved, 5314k data, 668k init)

Why my new linode has such a minor quantity of memory?

Linode support says that newer kernel may display less ram, but why it displays less ram?

Thanks.

Regarding the RAM, I'm pretty sure Linode has given you the exact same amount of memory but that you are using different kernel versions. (2.6.39 in particular started to reserve a lot of memory)

As for the CPUs, it's simply a matter of the host machines set up at different times, but should be fairly similar.

And 2.6.39.1 fixed it. 64 bit still eats more memory over 32 bit, however.

-Chris

Speaking of which, do you know if x86 and x86-64 both took a huge jump in reserved memory with 2.6.39 for different reasons or what the reason is that it was only fixed for x86?

Hi Caker, thanks for the answer.

I'm using the latest 2.6.39.1 64bit kernel from your list, so can I consider this normal?

EDIT: My old linode uses a 64bit kernel too. (2.6.35)

I think the original change that caused the increase in reserved memory was common, but the subsequent change that restored older behavior (and thus recovered most if not all of the change) was 32-bit only.

The thread at viewtopic.php?t=7229 contains a couple of details and external links to other info and kernel patches.

-- David

will we see a "fix" for 64bit kernel also?

Ask the kernel developers, not Linode.
Also, why using 64-bit kernel at Li512? Unless you're doing scientific, computation-heavy stuff, you're just wasting RAM anyway.

_________________
rsk, providing useless advice on the Internet since 2005.

I'm not asking to linode, I'm asking to who want to answer
I'm using 64bit because I don't need 512MB of RAM for the services that is running my linode and 64bit is more cool when ram isn't a problem

There's never too much ram for caching, you know.
Even without this "stealing 100MB bug" of 2.6.39, 64-bits just don't make sense on a Linode 512.
Weeeeeeird.

_________________
rsk, providing useless advice on the Internet since 2005.

It does not make sense if you need ram, my tasks doesn't need that ram.

Saied that do you know if kernel 3 corrected this bug?

Except that any free ram is used for caching and such, which means that it speeds your server up.

See www.linuxatemyram.com for details. Basically, Linux uses available RAM to cache things and improve performance. Less free ram equals less cache, regardless of the actual footprint of your running processes.

I don't need speed.

then why did you start this thread?

Because I never seen a kernel requires such a big quantity of ram before.