Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?
DEAL: For $25 - Add A Second Phone Number To Your Smartphone for life! Use promo code SLASHDOT25. Also, Slashdot's Facebook page has a chat bot now. Message it for stories and more. Check out the new SourceForge HTML5 Internet speed test! ×

Comment Re:Economics of that stunt are dodgy (Score 4, Informative) 206

You are simplifying it to such an extent that you completely miss the point. The cost of the fuel is a small fraction of the cost of the launch - the cost of building the 1st stage dominates. When that stage is destroyed, it is an operational expense for that launch. When it is recovered, it is a capital expense with an additional smaller operational expense to refurbish and another expense to account for the reduced efficiency of the launch (some fuel held in reserve as you say).

Since converting the huge operating expense into a a huge capital expense that results in an asset that can continue delivering value minus some small additional operating expense, the net result is a more economic system.

Comment Re:what (Score 1) 294

without NAT as a first but relatively porous line of defense against random packets coming in from the open Internet, it's necessary to be much more deliberate about which types of packets to accept and which to reject.

What? If you want the same 'security' as NAT, can't you just set the firewall to reject all incoming connections?


Comment In Canada (Score 1) 568

Each province typically has laws establishing professional organizations as the gatekeepers, so for example in Alberta the Association of Professional Engineers and Geoscientists of Alberta is legislatively in charge of engineers. The law protects the use of the title "Engineer" such that a lot of tech companies actually violate the law by having employees whose title is something like "Systems Engineer" when they are not in fact members of the governing society. And before you ask, yes, they do have provisions for Software Engineers but in Alberta at least that is probably poorly developed.

I'm always amazed at how US tech companies get away with having non-engineers titled as engineers.

Comment Re:SUSE is for cows. (Score 1) 31

Technically you just need to take some cell samples, say by swabbing the cow's cheek, then sequence the DNA, interpret the sequence. You might have to wait for biology to catch up to decode all the source code you've collected.

Comment Re:$480 million to fund managers (Score 1) 274

That is just crazy. These are not high-risk/return investments funds. Just load up on a diversified bluechip portfolio, and make sure you follow all the other sheep so that you can't be singled out for getting something wrong.

Will that strategy net you a 20% return on your investment? Because that's what Yale's fund managers achieved.

The bigger the fund the higher the percent returns, but that's not because they are better at "investing" (i.e. moving capital from losing companies in a competitive market to winning companies), it is because there are successively more exclusive financial instruments whose benefit to the market is successively more dubious but return higher and higher margins. In other words the system is gamed at multiple levels and the more money you have, the more exclusive gamed systems you get to play, and you pay the gatekeepers more and more, but hey "everyone" wins (where everyone means everyone at this level of exclusivity and higher).

Comment Re: Tell me about POWER and IBM. (Score 3, Informative) 85

I've been working with AIX since 1990. Prior to that a bit of SunOS. AIX is is different but generally well thought out. Most people who hate it simply aren't used to the differences. Lots of feature that we take for granted in today's Linux existed in AIX 25 years ago.

Tivoli Storage Manager is a dream. I remember setting up a high-availability TSM (well, ADSM at the time) server and having a client backup running during fail over testing. Client connection failed, continued retrying until the server was back up on the other node, then the backup continued where is left off. Transaction backup with rollback and resumption after server fail over! Try that with NetBackup or Networker or Avamar or CommVault.


Comment Re:Can we get a real Linux filesystem, please? (Score 1) 210

Btrfs, like ZFS and Netapp's WAFL, use a far more efficient copy-on-write strategy that avoids the write penalty.

WAFL doesn't do copy-on-write. Copy-on-write means a write to a block in a file requires the original block to be read, written elsewhere for the snapshot, then the new block written in the original location. That's exactly what WAFL doesn't do. WAFL writes all changed blocks for multiple files in big RAID stripes, updating pointers to current copies and leaving snapshot pointers pointing to old copies of the updated files. Very efficient for writes, but changes almost all reads, random or sequential (within a file) into random reads (within the filesystem) because file blocks get scattered according to write order, not location of the block within the file. That's why they want lots of spindles in an aggregate and they love RAM cache and flash cache.

But since you say that copy-on-write avoids the write penalty I think you know what is does but simply don't know that it isn't copy-on-write.

Slashdot Top Deals

Economists can certainly disappoint you. One said that the economy would turn up by the last quarter. Well, I'm down to mine and it hasn't. -- Robert Orben