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Comment Man Hours (Score 2) 233

To be quite frank, what you need are man hours. There are many tools out there that can help you finding corners or edges to start working on, but you can do the same with a coin toss, no tool will significantly reduce the amount of man hours that will have to be spent fixing, re-factoring and re-organizing. Take a good loooooong look, devise a simple strategy and then jump in somewhere. From personal experience, add lots of assertions as you go.

Comment Standardize a VM interface instead? (Score 1) 190

We see new languages all the time, most of them don't stand the test of time or are supplanted by others as time goes on -- but at this point there is a ton of industry experience in supporting a standardized Virtual Machine language / architecture / (whatever you want to call it). There's Sun/Oracle's JVM, along with several other implementations of this VM interface. The JVM will support any number of languages that target it. Microsoft has done this as well with their CLR (Common Language Runtime) as part of .NET. The web already has the "Object Model / Standard Library" end of things, the DOM, it just needs a virtual machine standard and then web developers could bring, port or invent the language of their choice.

Comment Everything. (Score 1) 2

If there is any question that a dependency might be unavailable for any reason at any time, for any dependency that is necessary include it. Put them all in an obvious "contrib" sub-tree and make it easy for someone building/using your software to "drop-in" an updated version of a contributed dependency.

Comment Re:That's great and all, but . . . (Score 1) 146

See page 3, the shm_use_phys #'s vs the other for FreeBSD. DragonFly does not see this hit because we _excessively_ cache pv entries (it would be nice if we could dial this back).

The performance difference here is identical to what this patch will cause.

Comment Re:That's great and all, but . . . (Score 5, Informative) 146

I just posted this to the blog, but I will repeat it here --

There is a very good reason we OS vendors do not ship with SysV default limits high enough to run a serious PostgreSQL database. There is very little software that uses SysV in any serious way other than PostgreSQL and there is a fixed overhead to increasing those limits. You end up wasting RAM for all the users who do not need the limits to be that high. That said, you are late to the party here, vendors have finally decided that the fixed overheads are low enough relative to modern RAM sizes that the defaults can be raised quite high, DragonFly BSD has shipped with greatly increased limits for a year or so and I believe FreeBSD also.

There is a serious problem with this patch on BSD kernels. All of the BSD sysv implementations have a shm_use_phys optimization which forces the kernel to wire up memory pages used to back SysV segments. This increases performance by not requiring the allocation of pv entries for these pages and also reduces memory pressure. Most serious users of PostgreSQL on BSD platforms use this well-documented optimization. After switching to 9.3, large and well optimized Pg installations that previously ran well in memory will be forced into swap because of the pv entry overhead.


Submission + - AMD confirms CPU bug found by DragonFly BSD's Matt Dillon (

An anonymous reader writes: Matt Dillon of DragonFly BSD just announced that AMD confirmed a CPU bug he found. Matt quotes part of the mail exchange and it looks like "consecutive back-to-back pops and (near) return instructions can create a condition where the processor incorrectly updates the stack pointer". The specific manifestation in DragonFly were random segmentation faults under heavy load.

Submission + - DragonFly BSD 3.0 Released (

dragonk writes: The first major release of DragonFly BSD in 10 months is now available. The major feature of this release is multi-processor performance and scalability, DragonFly is now able to claim par with its contemporaries under many workloads, while preserving the reliability its users have come to expect. See the release notes for the full scoop.

Submission + - DragonFly BSD 2.8.2 Released 1

An anonymous reader writes: The 2.8.2 release of DragonFly BSD is now available, featuring significant advances in multi-processor performance based on DragonFly's signature soft token locks. It also includes many feature advancements including: pf from OpenBSD 4.2, the Wifi stack from FreeBSD and DataMapper from NetBSD (with significant enhancements). This release also marks the return of the GUI image. See the release notes for full details.

Submission + - DragonFly BSD 2.8.2 released (

dragonk writes: The 2.8.2 release of DragonFly BSD is now available, featuring significant advances in MP performance based on DragonFly's signature token's, as well as many feature advancements including: OpenBSD 4.2 PF, FreeBSD-Current WIFI stack and DataMapper. See the release notes for full details.

UK Man Prevented From Finding Chipped Pet Under Data Protection Act 340

Dave Moorhouse was elated when he was informed that a microchip provider had information on the whereabouts of his stolen dog. This joy soon faded when the company informed him that it could not divulge the Jack Russell terrier's location because it would breach the Data Protection Act. Last week a court agreed with the chip company and refused Mr Moorhouse's request for a court order compelling them to reveal the name and address of the new owners. Steven Wildridge, managing director of the chip company said: “This is not a choice, it’s an obligation under the Data Protection Act. If the individuals involved do not want us to pass on their details to the original owner then we cannot do so unless compelled to following a criminal or civil proceeding."

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