Nordi, On Tuesday 11 October 2005 01:59, nordi wrote: > Randall R Schulz wrote: > > In all likelihood, the activities during system > > start-up are not characteristic of those performed during normal > > operations. > > True, but if the mere usage of ReiserFS slows down things by 23 > seconds on my box, don't you think there is _something_ wrong here? > That is a 40% difference! And assuming that the system also does lots > of non-fs stuff during boot, the performance difference is probably > even higher.
No. That conclusion _does not follow_ from the facts you have. It's not just a matter of "how much file system I/O" vs. "how much other stuff" it does. It's the nature of the activity, the size and placement of the files, the size of the I/O operations and whether access is largely continuous or not, whether it is aligned to page boundaries, the opportunity (or lack thereof) for concurrency in the code that drives the FS activity, etc. Very few people understand the complexity of performance analysis in modern computing systems. To think that one simple, uncontrolled experiment can tell you something about the inherent efficiency of a particular file system or implementation thereof or that it can be extrapolated to other contexts is simply incorrect. Is boot time the be-all and end-all of your system performance criteria? If so, then by all means, make whatever choices optimize it. But it's likely you cannot simultaneously optimize both start-up and normal operations. > Maybe ReiserFS is not a good choice for small partitions (my 4GB is > rather small, nowaday), or it is not a good choice on laptops, or > Suse sets something up incorrectly, or whatever. I think it would be > really interesting to find the answer to this question. Yes, it would. Especially if you include the null hypothesis "nothing is wrong." You're approaching this whole thing with an assumption that may or may not be the case. > Regards > nordi Randall Schulz --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
