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Putting Linux Reliability to the Test
Frank writes "This paper documents the test results and analysis of the Linux kernel and other core OS components, including everything from libraries and device drivers to file systems and networking, all under some fairly adverse conditions, and over lengthy durations. The IBM Linux Technology Center has just finished this comprehensive testing over a period of more than three months and shares the results of their LTP (Linux Test Project) testing."
Just put a link to each box on /. and wait 24 hours.
Anyone know if the test will be repeated with kernel 2.6.x?
You want to put any OS to the ultimate test, you should run cheap generic hardware. I swear it's an industry conspiracy that generic parts struggle a boat load. If your parts don't come from the big boys (DELL, gateway, etc), you are likely going to see issues down the line.
Get some ECS motherboard, generic RAM... bang. You're in for the evening.
> You're thinking Microsoft Works.
I'm thinking it doesn't.
Why do you trust IBM's Linux Technology Center to evaluate Linux?
I seem to recall getting random crashes with cheapo memory, and it was a pain to track down the offending component. Of course, one would assume that IBM wouldn't go for cheapo components, but still: how does one point the finger at the software, instead of hardware? Is it just repeatability?
This is nice to hear, but it would be even more valuable if the same tests were performed on a variety of operating systems in order to compare the results.
Brian
My Company
The Linux kernel and other core OS components -- including libraries, device drivers, file systems, networking, IPC, and memory management -- operated consistently and completed all the expected durations of runs with zero critical system failures. Every run generated a high success rate (over 95%), with a very small number of expected intermittent failures that were the result of the concurrent executions of tests that are designed to overload resources. How does that compare with other OS's?
Second off, If this were M$ testing 2k3 and publishing the paper, everyone here would be crying foul. But because its, "Linux" it must be 100% unbais and true.
I've been using Linux for 8 years now including under high stress enviroments, 3d graphics rendering mainly, and from experiance I have see very good things from Linux. We have had software glitches before, but the core software maybe has caused 3 - 5% of our downtime. Over 70% of our downtime involves human error and about 25% of failures are due to hardware giving out.
Still what my customers are wanting to see isn't benchmarks as "So easy Grandma could use it" in Linux. While the people in the datacenters want to know how well Linux will bear under a load, most end-users and SMB's don't need to worry about it, they just need something easy to use that works.
"The problem with socialism is eventually you run out of other people's money" - Thatcher.
2.6.0 has only been out for a week. I'm going to want to see someone stress test it for a hell of a lot longer than a week before I call it "enterprise ready".
The people performing it have a vested financial interest in having it turn out a specific way, notably positive. If the test resulted showed poor reliability, then I would understand trusting it because it would go against the motives of the people performing it. Since the test affirms their business model, no matter how documented it is, it should be suspect.
It doesn't appear to be a test rigged to make one platform look better than the other.
It looks a bit skewed to me. Many of the test results depend on the computer systems meeting expectations of the people testing it, particularly in overload cases. Since the people who tested work in the Linux Technology Center, their expectations stand a greater likelyhood of being consistant with the system.
Take C/C++ and Java. Someone who regularly works with C/C++ knows certain libraries (notably the character ones) return ints for status in the form 0 being false and not 0 being true. If someone expects that, the system meets expectations and passes. If someone comes from a different background, say Java, he or she may not expect that, and the system would consequently fail the test of meeting expectations. I would like an evaluation from somewhere in-between, not someone whose years of experience allow them to gloss over what might be problems for another person.
Microsoft commonly hires outside companies to perform their tests. Do you remember the evaluation of Exchange versus Notes/Domino scalability by Ziff-Davis but funded by Microsoft? People justifiably questioned those results, as the company hired (Ziff-Davis) has an interest in pleasing the hiring company (Microsoft) so they get future work.
They have much to gain: more corporate customers and more respect and funding by greater IBM. Just because IBM supports Linux doesn't mean its motives are pure (not financially driven). Another reason for bias is the division also stood to have huge setbacks if the tests were unfavorable. How could they justify expansion and better funding if their previous statements about Linux being enterprise-ready were unfounded?
- because the test methodologies are documented
- because it's disclosed up-front that it's IBM Linux Team testing Linux (ie no hidden conflict of interest
As opposed to the usual (ie in the Microsoft World)Visit CryptoGnome in his home.
So, ya reply to one point but ignore the rest? I think his (ultimate) point is valid. If the test was rigged, the folks involved with developing the kernel would catch on and take IBM to task for fudging the results. No, I'm not talking about the Slashdot/Fark crowd. I'm talking about REAL developers.
Also, Linux has weathered some unfavorable (and honost!) critiques before. Linus Torvalds said it best when he said (and I paraphrase since I am too lazy ATM to look up the actual quote) that it doesn't matter if there's negative publicity in the press about Linux. It just meant he got his bug reports from the Wall Street Journal as opposed to the regular kernel mailng list.
--- Journals are boring; Go to my web page instead
95% success ratio... does that mean that 1 in 20 programs I run segfaults or what? What do they mean by "failure"? Not finishing given task in predefined time? Getting the results wrong? Hanging?
Sorry but that means nothing. Even if there -was- a comparison to other systems, it would still mean nothing. 95% success ratio, 78% happiness factor and 93% user satisfaction.
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
I think IBM used SuSE instead of Redhat because IBM Global Services and SuSE have been partners for almost two years.
Maybe you should stop hmmmmm'ing about these great mysteries and start googling.
Beware blue cats moving at
Hardware fails in random patterns (bits flipped by beta radiation, for example), software fails the same way in controlled instances (the same flawed logic fails the same way each time).
So when you run a test 5 times, and you get 5 results, the hardware is broken. When you run the same test 5 times, and it gets to the exact same point before sig11ing, you have a software flaw.
This is also why you do multiple tests to ensure you're getting an accurate picture of what's going on (flawed or not).
--
Internet Explorer (n): Another bug -- that is, a feature that can't be turned off -- in Windows.
This test would have been more interesting if there had been failures. Perhaps they could have tried the test on an older version of Linux, or a different operating system.
I have been trying to write some tests of my own recently. So far I have found a filesystem OOPs, a ptrace BUG(), and my system locks up on low memory situations. Probably the lockup is because my ethernet driver allocates memory in the interrupt handler (GFP_ATOMIC) and can't handle the result when there is no memory available.
I need to fix the lock up first of all so the other tests have time to run...
FTA
The tests demonstrate that the Linux system is reliable and stable over long durations and can provide a robust, enterprise-level environment.
Ok, now i dont mean to troll here, so mod down if you wish, i really dont care.... BUT...
I am a linux user/programmer/lover for the past few years now, and i wanna see a company that is not SO IN LOVE with linux say what have just been said by IBM above.
In other words, i dont want to see companies who sell Linux, or who have benefit in selling Linux praise it. Does any one of you know of someone who fills in these criteria. Sun for one is not very fond of Linux, nor is MS ofcorse (despite the fact sometimes i doubt they have code in their stuff from Linux...)...to make a long story short
It would be really nice if such a judgment came from someone else besides IBM/REDHAT/ORACLE...
The lunatic is in my head
"The Linux kernel properly scaled to use hardware resources (CPU, memory, disk) on SMP systems."
Sorry, but how can the scaleability of the CPU resource be proven on a 2 CPU system? Show incremental results on 1, 2, 4, 8, 16, 32 etc. etc. and then CPU scaleability may be proven.
This is NOT an anti-Linux troll, rather the evaluation needs to justify it's outcomes or it starts to look like something from a company starting with M.
1) Linux is free if your time is worthless
2) My time is not worthless
3) Linux is not free
4) Giving Linux as a Christmas present is not "cheap"
5) Linux is a good Christmas present.
All that this shows is that a Linux based system works in the way that it should. Would you expect anything else if you ran your: TV, central heating, ... for a long period ?
The trouble is that, after a period of increased stability in the 1980's, in the last decade people have come to expect that computers fail, and they wonder with amasement if they don't.
OK: 30 years ago I remember it being a good day if the mainframe stayed up 12 hours. But things have moved on, today you expect your: MVS, VMS, Unix, Linux machine to stay working. The only OS vendor who's products have not matured is the one in Redmond - largely because of rampant infestation with new features.
The above is not intended to belittle the fantastic efforts of all those involved.
In fact, it's not much of a question for me anymore -- when there's a problem, it's normally hardware malfunction. I have several machines with 160+ day uptimes, which would be longer if not for an extended power outage at the office.
IBM just confirmed what I already knew. Guess what, Win2k is pretty stable, too. Sorry, but it's true.
But, jeeze, isn't anyone else drooling over those systems they tested on? Makes me hate my busted whiteboxes and horrible HP's a little more everyday.
Repeat after me....."MMMM, dual Power4......MMMM, dual Power4...."
The very reason Linux has already made so many inroads into coporations in the first place is because of its reliability and stability, and not because some marketing campaign has churned out the words on header paper.
Another point is that I personally expect the sytems I administer to run for a darn side longer than 30, 60 or 90 days unless I need to restart them because of a kernel upgrade. When my last bunch I worked for went tits-up, our SAMBA file server had a 790 day uptime, and had run the SAMBA daemons reliably throughout, as well as doing internal DNS and DHCP. That's what your average Linux sysadmin expects from a Linux server box.
A Linux desktop being used for all manner of things though is completely another story: if I muck around with the Linux install on my laptop, as I do because that's what I do, then I expect to break it from time to time, and so "reliability" is not measured in the same way on a desktop/laptop system, IMHO.
The ideal environment for Linux is as a networked server, where it can get on with doing what it was setup to do, and will continue doing so until someone pulls the power plug on it. In that context, there are few OS's playing on the same field that can rival it for reliability and stability.
but with package and dependency madness.
I couldn't tell you the number of times I tried to install something and it fails because I was missing "X-Widget-2.41.so.1", so I try to install that "X-Widget-2.41" package and the "X-Widget-2.41-devel" package and they fail because they are missing several other depends as well.
Linux stability is fine. The GNU software stability is fine. We need a better way to install and maintain software.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
I've been using an old P120 laptop as a firewall/router for my house for the past several years running 2.2.something. I wondered why it rebooted after noticing an uptime of only a day or two, but found that instead I was experiencing the uptime rollover bug (at about 500 days; Windows used to crash on a similar bug after 48 days). About a month ago, it stopped giving out DHCP addresses. I went downstairs to investigate, as I couldn't log in remotely, and found that the hard drive was making that nasty clicking sound. I eventually managed to ssh in (sshd and sh were in ram; I just waited for the logging to time out). I was able to kill syslog and cron, and now dhcp is again giving out addresses.
It's been running just fine for a month now with a dead hard drive.
(Yes, I'm getting a replacement because it won't survive an extended power outage on that ancient battery.)