Author Archives: Chris Samuel

btrfs RAID1 benchmark on Dell E4200 with 128GB SSD

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Having previously posted some nice XFS Bonnie++ numbers on the work Dell E4200 I use I thought I’d redo these after having migrated to a RAID-1 configuration of the experimental btrfs filesystem. As SSD’s are not necessarily as reliable as spinning disk yet for data integrity I wanted a system that could spot this and correct for it, so I created two equal size partitions on the SSD and created the filesystem with mkfs.btrfs -d raid1 /dev/sda10 /dev/sda11 before mounting it with the ssd mount option.

Version 1.03c       ------Sequential Output------ --Sequential Input- --Random-
                    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP  /sec %CP
sys26            2G           27458  23 21782  19           108478  39  3079  21

                    ------Sequential Create------ --------Random Create--------
                    -Create-- --Read--- -Delete-- -Create-- --Read--- -Delete--
              files  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP  /sec %CP
                 16  7542  99 +++++ +++  5818  99  7232  99 +++++ +++  5638 100
sys26,2G,,,27458,23,21782,19,,,108478,39,3078.8,21,16,7542,99,+++++,+++,5818,99,
7232,99,+++++,+++,5638,100

real    3m30.808s
user    0m0.404s
sys     0m55.599s

Whilst the raw numbers are nowhere near as good you have to remember that this is doing checksumming of all the data and mirroring it across the two partitions I created for it and, if it finds a problem with the data, will try and recover using the data on the other partition. It’s also still in development!

Propaganda and Gaza

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There’s an interesting article by a BBC correspondent on the BBC website talking about “Propaganda war: trusting what we see?” that raises doubts about the veracity of a YouTube video put out by the Israeli government claiming to show a rocket attack on a lorry being loaded with Grad missiles.

The Israeli human rights group B’Tselem though disputes this story, itself claiming that it was a mistaken attack on a lorry being loaded with oxygen cylinders by Ahmed Sanur, his family and workers – at which point the Israeli’s changed their tune:

The Israeli response was that the “materiel” was being taken from a site that had stored weapons.

Sadly the Israelis are deliberately making it hard for people to confirm or refute their claims:

Israel has bolstered its approach by banning foreign correspondents from Gaza, despite a ruling from the Israeli Supreme Court.

which immediately makes you wonder what they’re trying to hide.

Unfortunately as the reporter is being critical of Israels policy of denying foreign correspondents access he gets accused by readers on that article of trying to side with Hamas (same strategy as accusing those being against the stupid useless mandatory content filtering proposal here in Australia as being pro child porn), which obviously gets his goat, his response to that is:

I do not believe anyone’s “propaganda.” We seek to verify all claims, from whatever source. One of the main claims in Gaza at the moment is the serious situation for the population. Having reported from Gaza many times over the years, I know how crowded parts of it are and how dependent the people are on food aid from the UN. This means they have no other source of supply but equally, if the system is working, they should be getting enough to get by on. The problem is that foreign correspondents cannot get in to establish the exact situation for themselves.

Before I get accused of similar pro-Hamas leanings I’d just say that I consider all violence by both sides to be wrong, unjustified and completely counter-productive. As Ghandi said “An eye for an eye, and soon the whole world is blind”. I have my doubts that there will ever be a lasting peace in that area. 🙁

Redacted NSA Cold War History Released

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Via Bruce Schneier, a redacted version of the NSA’s “American Cryptology during the Cold War, (1945-1989)“ has been released thank to a request from the George Washington Universities National Security Archive project.

It includes a rather interesting section (book 1, pages 18 and 19) on how, in 1947, the UK foreign intelligence agency, SIS, decrypted some KGB messages from Canberra that turned out to include classified UK intelligence military estimates. This caused the US to break off crypto intelligence sharing with Australia putting the British in an awkward situation; as Clement Attlee put it:

The intermingling of American and British knowledge in all these fields is so great that to be certain of of denying American classified information to the Australians, we should have to deny them the greater part of our own reports. We should thus be placed in a disagreeable dilemma of having to choose between cutting of relations with the United States in defence questions or cutting off relations with Australia.

It took 5 years, the establishment of ASIO and a change in government from Chifley to Menzies before the US would reestablish full resumption of cryptologic exchanges with Australia and the author of the history concludes that this has a very bad effect on early American intelligence efforts against China.

The cause of the original leak to the KGB ? Two “leftists” in the Australian diplomatic service…

Ubuntu Intrepid Packages for Digikam 0.10 (KDE4) (Updated)

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Finally I’ve stumbled across packages of the KDE4 version of Digikam (0.10) which is currently in beta.

deb http://ppa.launchpad.net/digikam-experimental/ppa/ubuntu intrepid main

They’re part of the Digikam Experimental Personal Package Archive (PPA) and so track the latest development releases (0.10.0-rc1 as I write this) and work for me on Ubuntu Intrepid with KDE 4.2 (at the moment) – remember to install Marble!

Note

Many thanks to Maarten Fonville who previously provided packages that this story originally pointed to, and who commented with the above alternative archive.

Rogue CA – MD5 collisions for phun and profit

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Now this is, umm, interesting..

We have identified a vulnerability in the Internet Public Key Infrastructure (PKI) used to issue digital certificates for secure websites. As a proof of concept we executed a practical attack scenario and successfully created a rogue Certification Authority (CA) certificate trusted by all common web browsers. This certificate allows us to impersonate any website on the Internet, including banking and e-commerce sites secured using the HTTPS protocol.

Trust no one..

(Via)

Australian Android Phone

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Kogan, an Australian company who usually specialise in LCD’s, are making a mobile handset (the Agora) for Google Android (which uses the Linux kernel) with 3G, quad band GSM, GPS, wifi, Bluetooth, etc… It’s due to start shipping at the end of January and I’ve just pre-ordered mine to hopefully provide a more functional open source phone and let me hack more with my OpenMoko phone without having to worry about not having a working phone.

Kogan Agora Pro mobile phone