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Comment: linus was right (Score 2, Interesting) 757

by MagicMerlin (#49228349) Attached to: Was Linus Torvalds Right About C++ Being So Wrong?
Linus was right (I didn't agree with him when he wrote that but I do now). Jeff doesn't answer any of the major issues with c++: Lack of standard ABI (preventing interop with other languages), insanely complex grammar, years of paradigm shift, action at a difference, lack of abstraction away from computers, etc. Java/C# have completely displaced it in the business world and C still dominates system programming. C++ would be already obsolete except that it caught a big with the gaming industry...real-time games can't tolerate GC languages and C is considered too baroque to many developers.

Comment: Re:HDD is fine for .. 98%? (Score 1) 256

by MagicMerlin (#46781581) Attached to: SSD-HDD Price Gap Won't Go Away Anytime Soon

Lets be honest here - outside of a small percentage of users doing raw uncompressed video operations HDD are more than fast enough. Drives and OS both offer large caching of high use objects which reduces seek/startup time differences to a very small amount. The biggest difference is on start up and even there.. do those 5, 10, 15 secons extra really matter that much? How often are you booting? Or even resuming from hibernation if thats your thing?

As to power, idle is now around 5 or 6 watts and standby around 1. Even in a laptop the difference in power use between hdd/sdd is not going to make or break the deal. Your screen, however, another story.

That's silly. Anyone who does anything on their computer besides browsing the net and email will quickly observe that the move from slow to fast storage is the single greatest performance improvement in the history of the computer. It's very simple: if you are writing any non trivial amount of data or you are reading from datasets that exceed unreserved ram (a very typical thing to do that is gaming) then the hard drive is the primary performance bottleneck in the computer.

Comment: Re:duh (Score 1) 256

by MagicMerlin (#46781485) Attached to: SSD-HDD Price Gap Won't Go Away Anytime Soon

disks (and to some extent tape) will always have scaling advantages over litho-fabed storage

I could not disagree more. Disks spin and have some complicated assemblies and pricier raw materials. The main cost inputs to SSD are capital investments (which amortize to zero over time) and energy. There is a lower limit to density in flash (which AIUI we are already close to) but flash is already denser than hard drives. Tapes have an advantage in that they are not active and so are very cheap for offline data. Disk drives OTOH have no fundamental advantages over flash -- they are being rapidly displaced for user facing devices. Warm storage (NAS etc) where SSD performance don't play will take longer -- maybe 3-4 years and it's done.

Comment: Re:We live like kings and queens already (Score 1) 256

by MagicMerlin (#46781387) Attached to: SSD-HDD Price Gap Won't Go Away Anytime Soon
moreover, storage is specializing. desktop/portable computing devices of all types are only going to be sold with SSD Real Soon Now (in many cases this has already happened). Hard drive storage is going to be primarily be used for dedicated storage appliances. This has already happened to a significant degree in the enterprise depending on how progressive the IT dept is.

Comment: not that simple... (Score 1) 48

You can have both. Let's take transaction time performance for example -- bitcoin does not provide fast resolution (compared to, say, the visa network) but nothing is keeping a transaction broker from laying on top and providing those services. A 'bitcoin visa' payment service would then provide near instant times, allow for chargebacks, etc by absorbing the risk through fees and making a profit on the difference.

Comment: Re:Not for MtGox but kinda agree (Score 1) 81

It's called an ID for a f***king reason.

And (amount, address, timestamp) as a key? That's funny sh*t right thar!

I mostly agree, but only because of the timestamp. Timestamps make poor keys for various reasons. A little trivia: that's my blog post :-).

Comment: Re:The consumer trend seems to be clear (Score 1) 263

by MagicMerlin (#32825464) Attached to: SSDs vs. Hard Drives In Value Comparison
I used to say the same thing, but unfortunately it's not so clear cut. The intel drives which post such great random i/o numbers only do this because they are configured in write back cache mode w/volatile cache. The x25-M in write through mode can post about 50iops writing -- I'm not kidding. Also, wear&tear on the drive is much higher. IOW, the intel controller does not perform magic -- they cheated. The x25-e drive is configured the same way -- the performance drop for going to write-through is not so high (you can eek 1000ish iops out of a drive) but the drives are expensive and the the math doesn't work out all that well. The basic problem is that flash is plain and simply lousy at random writing just like hard drives. With a small NV cache on the drive, things could be completely different (and some boutique mfg IIRC already offer this) but until you see Intel, Seagate, or WD on a drive with NV guarantee for at least semi-reasonable price you will not see serious intrusion into the enterprise.

Comment: Re:Our approach (Score 1) 244

by MagicMerlin (#32581388) Attached to: Kaminsky Offers Injection Antidote
for the cases that you can't strictly do the query, we push the logic into a function call and dyna-sql it. (to hide the internals, it's actually mostly function calls over the low security interfaces). we also wrote a libpq wrapper to allow sending and receiving extremely complicated structures over libpq protocol efficiently. (here, if you're curious:

Comment: Our approach (Score 1) 244

by MagicMerlin (#32579078) Attached to: Kaminsky Offers Injection Antidote
We use PostgreSQL. We expose the libpq not default port directly to the internet through pgbouncer. What we did:

*) Modify pgbouncer to only except extended protocol (parameterized) queries
*) Auto Generate list of allowed queries used by app to store in whitelist
*) Block all functions except auth if authenticated or to the whitelist othewise
have had zero problems. curious what you think.

Comment: Re:postgres didn't do so badly (Score 3, Informative) 157

by MagicMerlin (#32550426) Attached to: MySQL Outpacing Oracle In Wake of Acquisition
Postgres has traditionally had lousy replication options. This of course is going to change with 9.0 hs/sr. Older versions of postgres (pre 8.x) had some operational difficulties that made it an awkward fit for high transaction load web environments. Now that those downsides are pretty much eliminated, it's about the best general purpose sql database out there -- it has many niceties/features that are rare/non-existent elsewhere. Transactional ddl for example.

"Most of us, when all is said and done, like what we like and make up reasons for it afterwards." -- Soren F. Petersen