That's not quite what I meant.<br>The "add-on" source can't really be the same as the "built-in" pre-compiled modules.<br><br>One very important reason is that the "built-in" version comes with the modules
<br>"kmp-default" and "kmp-bigsmp" which the "add-on" source can't possibly provide.<br><br>these are specialized versions of the kernel, which are not part of and cannot be part of the source
<br>or rpm add-on packages.<br><br>There must be a performance difference or "lower-level" (raw) access difference between the two.<br><br>for example: as a service, you can actually kill a service (kill -15 if you have to),
<br>but the kernel can't be killed (at least not without killing the whole system).<br><br>the other part is the boot process, which is mentioned, but using boot.local is not as good (IMHO).<br><br>I've seen some performance differences between them, but that could be due to crappy hardware ;)
<br><br><div><span class="gmail_quote">On 2/11/07, <b class="gmail_sendername">Armando Ortiz</b> <<a href="mailto:armandoo@verizon.net">armandoo@verizon.net</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Dan Gahlinger wrote:<br>> I have a question which perhaps many people might have,<br>><br>> Is there any performance or reliability difference between using the<br>> "add-on" drbd source download<br>
><br>> or using the "built-in" kernel modules in Suse such as<br>> "kmp-bigsmp" and so forth?<br>><br>Other than being, perhaps, architecture-specific, I honestly don't think<br>you'd get much performance out of it. Most of the performance issues
<br>are relative to the underlying hardware - harddrive read/write speed vs.<br>network bandwidth.<br>> I noticed in Suse 10.2 they not only include the RPM of DRBD,<br>> but they also include two other packages which are NOT included if you
<br>> just use the source. they are "kmp-default" and "kmp-bigsmp" (there is<br>> a third, but I don't use it, it is "kmp-xen").<br>><br>I am also running OpenSuse 10.2 with DRBD as fileservers, but I
<br>installed the pre-compiled modules as opposed to doing the source<br>myself. It was much easier, and quicker, to set up.<br>> I was just wondering about reliability or stability differences<br>> between them?<br>
> I'm thinking the built-in would be preferable. Why? because it got me<br>> to thinking about booting.<br>><br>> When the system boots, one of the first things it does is mount the<br>> filesystems (fstab),
<br>> but the drbd volume is an EVMS which means it needs drbd running in<br>> order to mount it.<br>> But it seems to become a catch-22.<br>><br>> You can't mount the volume without drbd running, and you cant run the
<br>> drbd "service' (add-on) without mounting the filesystem. Which is<br>> where the kernel modules, and specialized kernels come in, they'd get<br>> loaded with the kernel.<br>><br>You could try mounting these via
boot.local instead of fstab so you can<br>do any last-minute autoprepping before the system is up and running,<br>which includes starting servers that might use the facilities after<br>they've been made available.<br>
> part two is - as a "built-in" it's part of the kernel, specially<br>> compiled, which means its a bit "lower level" than just a service.<br>><br>> or am I completely off-track here?<br>
I'm not quite sure what you mean by a 'lower level' than just a service<br>- whether or not you compile a module outside of the distribution vs.<br>using one provided for you as somewhat irrelevant, no???<br><br>
This is the beauty of tracks - if you get off of one of them, you can<br>easily jump on another... ^_^<br><br></blockquote></div><br>