No Comment

Sorry about this, but the Spam Monsters have been busy once more, flooding this site with spurious sign-ups and a torrent of spam comments.

In response, I’ve had to stop any new sign-ups, and I’ve also disabled commenting.

Hopefully, it’ll be temporary. In the meantime, you can email me if you want to comment on something.

Archibald Primrose, cut-throat, thief and leader of the infamous Slethwick Street gang of nineteenth century East London pick-pockets was…

Er, no.

Sorry… wrong notes. That’s actually Archibald Primrose, 5th Earl of Rosebery, sometime Prime Minister of the United Kingdom of Great Britain and Ireland (as it was back then).

An easy mistake to make, I rather think, all the same.

Anyway, “Slasher” Rosebery makes it to these pages because his name is associated with the secondary storage server a Data Guard environment will need to use. In the language of this blog, Rosebery is to Asquith what Balfour is to Salisbury: the secondary server in an Active Data Guard configuration using ASM via iSCSI shares. A new article on how to build one has just gone up.

Penny Dropped

I can’t say I fell in love with Windows 8.0. It is faster than Windows 7 to boot and feels generally a bit more responsive and ‘tight’. But the godawful Start screen method of launching applications was a real put-off: need to open a text editor so you can type some SQL to be pasted into a command window? Here… let me obliterate your screen with an intrusive chunk of purple sprayed with all manner of childishly-large and mostly irrelevant icons and see if you can hunt-and-peck for the application you want:

No thanks.

Of course, I was told I was doing it wrong: just tap the <Win> key and then start typing the name of your program. Windows search would find it and then you’d be able to launch it without hunting for anything… without touching your mouse at all! True, that: except that I might well not remember the name of the program I use to do stuff with. “VMware” I can manage; but having to type “calibre” instead of “ebook” for my e- book reader? Not so hot.

Happily, there were ways out of this impasse: Classic Shell gave me back a usable Start menu, so that it was possible to spend about 99.8% of my time without ever having to invoke the Start Screen at all.

But, you know… Microsoft had a point: poking your way through a large menu of program shortcuts can be a bit of a pain at times. So, I’ve gotten into the habit of pinning commonly-used programs onto the Taskbar (as I expect a lot of us have) and also to using the free Fences program to enable me to have a lot more launch icons on my desktop in manageable groups. In just a couple of hours of fiddling around, I’d end up with a Windows desktop looking something like this:

Granted, you might not like my choice of wallpaper… but at least my programs are readily-accessible and their shortcuts organized in a vaguely meaningful way.

However, there are a couple of things wrong with this. First, the free Fences program is no longer current. The developer, StarDock, now produces Fences 2.0, which isn’t free at all (though there’s a trial version). So hooking myself up to an end-of-life program (which I know already, in fact, doesn’t run well in Windows 8.1) isn’t the smartest move I ever made. Secondly, whilst Classic Shell is free and under active development, should I really trust a third-party developer to replace such core, low-level O/S functionality? For about a year, the answer to that has been a definite ‘yes’, but it’s niggled me a bit at the same time.

But you know what the biggest problem with that last screenshot is? (Apart from my choice of wallpaper, I mean!) It’s the fact that I have very carefully and very deliberately sprayed a bunch of icons all over my full-screen desktop and then organized them into groups. And isn’t that -at least in part- pretty much precisely what the Start Screen does in the first place? And if that’s even partially true, haven’t I just spent quite a lot of time in going out of my way to re-invent exactly what Microsoft already provides?

Well, not quite. Compare my two screenshots above, for example, and you’ll see that the Start Screen is bright purple and that the icons aren’t particularly well grouped or organized. It’s therefore intrusive and difficult to use (for me, I hasten to add). But if you could (a) get the purple to change to something that looked more like my desktop wallpaper; and (b) come up with a way of easily organizing those icons into the same sort of groups as I used Fences to create… well, then wouldn’t I have the desktop and program launcher I currently use, but without the reliance on third party software?

The penny dropped for me this week, in fact, that that’s indeed the case. And the Windows 8.1 RTM version that was finally released on Technet a few days ago provides exactly those two features I needed: you can now set your Start Screen background to be whatever your Desktop is displaying and you can right-click anywhere on the Start Screen, click the Customize button and move your launcher icons around into meaningful groups.

So here’s my actual (i.e., physical) Windows 8.1 desktop:

…and I have to say that it’s already a lot cleaner than before. But (the real test!), how’s my Start Screen look? Like this:

Sharing the same background as my desktop and organized. I’ll even argue that the ‘childish-looking’ icons are rather easier to see, read and use than the traditional icons shown in the second screenshot of this article earlier.

Is it perfect? No, definitely not. For a start, it’s harder to organize those icons than it ought to be, even with the new right-click/Customize option. Second, I could wish for ‘horizontal organization’ of the icons: there are five vertically-defined icon groups in that last screenshot -but the ‘Games’ one only has two icons. Couldn’t I move it to sit underneath the ‘Internet’ group? Not allowed, unfortunately, so things end up being a little less compact than I’d like.

Also, Microsoft brings up the Start Screen with a subtle animation that, despite its subtlety, annoyed me: pressing the <Win> key (or clicking the newly-restored Start button), it felt like something was being drawn over the top of the desktop, rather than it just being an invocation of a full-screen application launcher. Happily, that one is fixable: Control Panel → System and Security → System → Advanced System Settings → Advanced → Performance Settings and disable the option Animate controls and elements inside windows. Now invoking the Start Screen makes it appear instantly, as I think it should.

So, I guess my point is that when I read about Windows 8.1, the big story was ‘the return of the Start Menu’. Or at least the return of the Start button. Fine: I find clicking it or pressing <Win> about equally productive, so it’s no big deal for me one way or another. But finally grasping how to organize the Start Screen in a way I’ve been doing on my desktop for years; and not having a lurid purple pop-up appear, but rather a continuation of my desktop wallpaper theme… well, that for me is the big story in Windows 8.1.

I’ve therefore finally ditched Classic Shell and Fences, and feel I’ve lost nothing of what I was functionally doing before. I am left with that tighter, sharper, faster O/S that version 8 always was when compared to Windows 7, and the Start Screen is no longer the bugbear it once was. Search is much improved (without the arbitrary classification into Apps, Settings and Files), and the ability to boot direct to the desktop is also welcome. I am still utterly underwhelmed by the new-fangled ‘Modern Apps’, and their design æsthetic seems to me just peculiar. I accordingly wish there was a one-click way of associating file types with their old-fashioned desktop programs so that I’d never have to meet a Metro App in the flesh again. But there isn’t, so it’s a question of making your file/program associations one by one as they arise. Annoying, but not a show-stopper.

Anyway, I think this week I finally ‘got’ what Windows 8.x was all about, and 8.1 makes it a lot easier to use. I would certainly recommend it as a client desktop O/S, anyway.

A Bit of Parity

This sort of thing happens quite a lot to me:

That’s output from a FLAC-checking program called AudioTester. It means that an audio file is now corrupt or damaged in some way -and I can promise you that it didn’t start life that way, since my ripping program is set to verify its output before claiming it’s worked. Somewhere along the line, for whatever reason, a bit of “bitrot” appears to have crept in -and, as I say, that’s happened to quite a few of my 40,000+ FLAC files over the years.

My usual response in the past has been to re-rip the affected tracks, of course… but finding the right CD amongst so many candidates can be a right pain. So I wondered whether there was an alternative, and naturally there is. It’s called ‘parity information’: at the time of ripping the CD, you also generate a parity file that can be used to repair files if they are later found to be defective. It’s a bit like RAID-5, but at the file level, rather than the storage device level.

To generate the partity information, I use a program called Multipart. It’s only a 500KB or so zip download. (It’s official download page takes you to pages written in Japanese, and although there are instructions on how to click in the right place, it’s all a bit weird and I prefer having my own copy available from the first link, should I need it in future. Happily, it’s GPL licensed, so I can redistribute it without drama).

The help and documentation on Multipart is not that great, so let me give you a quick walk-through. Here’s a set of music tracks I ripped earlier:

bitrot02

Now, I’ve tested all those FLACs with AudioTester, so I know they’re good and I want to be able to keep them in that state. So, I download the Multipart zip file and unzip it somewhere; then I can launch the MultiPar.exe executable (in other words, there’s no installation routine to go through; just unzip and launch):

bitrot03

(Click on that to see the thing full-sized). You click [Browse] to point it to the directory containing all the ripped files. Notice it’s found the ‘folder.jpg’, not just the FLAC files: this thing computes parity data for any files it’s pointed at, not just audio files.

Then you use the Redundancy slider to set how much parity data you want to collect. In my case, I’ve set it to about 10% -meaning that the parity file will be about 1/10th the size of the original FLAC files. This also affects how much damage can subsequently be repaired: if the redundancy is 50%, then you’ll be able to cope with about half your data being corrupted. There’s no ‘right’ answer, just a trade-off between file size and anticipated damage amounts. In my case, my FLACs only usually get corrupted in one or two blocks at most, so 10% is probably ample.

Next, I click the [Create] button, and MultiPar scans all the files in the directory and generates parity data for them:

bitrot04

At the end of the process, you acquire a couple of new files in the chosen directory:

bitrot05

You’ll notice one of them is very small (just 21KB in this case), and the other is quite big: about 8.6MB here. The first just describes what files have been scanned to create the parity file; the second is the parity file itself. You’ll also note that 8,674KB is just about 10% of the sum total of the 6 FLAC and 1 JPG files that have been scanned (84,584KB by my maths). That’s the result of me selecting 10% redundancy earlier.

All I now need to do is to repeat this collection process for each CD rip folder in my collection -the nice thing about MultiPar being that it’s quite happy to traverse an entire directory tree, complete with lots of per-album subdirectories, generating per-album parity files as it goes. It will take a while, but given my CD rips currently occupy about 750GB, for a modest investment of a further 75GB, I can protect all my music files from damage, so long as that damage doesn’t extend to more than about 10% of any one file. Of course, the time to calculate the parity data is after a nice, fresh, validated rip… it’s no good me collecting parity data for files which have already been damaged!

Let’s pursue this example though. Suppose I were now to damage one of the 6 music files you see above… how would my prior collection of parity data help? Well, first, let’s do some damage: I’ll use the tiny (and free!) hex editor XVI32 to open up track 3 of the previous rips:

bitrot06

Obviously, a hexadecimal representation of audio data doesn’t make a lot of sense! But let’s just concentrate on that line I’ve highlighted: 5CAA2C. You’ll note it contains all sorts of hex-y data. Let me edit that to be a set of zeroes:

bitrot07

Hit the save button after that, and I’ve now got a FLAC file that’s had a small part of its internals zapped! You can tell it’s damaged, because the AudioTester program doesn’t like it any more:

bitrot08

So, can my earlier-generated parity information help me recover from this Frame Checksum error? Sure: all I have to do is to right-click on the smaller of the two parity files I mentioned before and ask to open it with MultiPar:

bitrot09

Note how the program correctly identifies track 3 as being ‘damaged’ -but, since only 0.2% of blocks are damaged, the 10% parity data is more than enough to permit a repair. (Thumbs.db is also declared to be ‘missing’, and the fact that it’s displayed in red indicates it’s actually a file that wasn’t there when the parity data was calculated -not surprisingly, as it’s a Windows system-generated file. It’s presence in that dialog is therefore irrelevant).

So all I have to do is click that [Repair] button on the lower-right, let the MultiPar program compute the lost data from is parity data files and, Lo!

bitrot10

…now it reports track 3 to be ‘repaired’. But is it really? The only way to check is to re-open it in XV132 and check that row 5CAA2C once again:

bitrot11

…and sure enough, there are now proper values for the cells in that row, rather than the series of zeroes I’d saved earlier.

Again, I stress that the parity data allows MultiPar to put back any data in any type of file. It’s not editing or manipulating audio data particularly -it’s just able to work out, via parity calculations, what the blocks of binary data in a file ought to read, compared to what it’s actually reading and thus to set it back to what it ought to be. So it’s quite a useful way of protecting any set of data -such as photographs, video, e-books, PDFs. Anything, in fact, where the deep-down integrity of the data matters to you (and you don’t have a file system -like ZFS- doing this sort of parity checking for you automatically).

If only I’d thought of doing this at the time I originally ripped my CDs :-( There is nothing that can now rescue the bad bit of Schubert I started this blog with (except a good backup, of course). But at least I can now prevent any new nasties creeping into my recordings over time, for a modest expenditure of disk space.

Spring

Australia is slightly weird in the way it has ‘decimalised’ the seasons, I think: It’s September 1st, therefore it’s officially the first day of Spring (and we won’t let minor astronomical inconveniences like the equinoxes get in our way). Likewise, 1st December will be the start of Summer; 1st March the start of Autumn and so on.

Anyway, even though the lack of astronomical relevancy annoys the hell out of me, it’s true that Spring has definitely sprung: we spent today in 23 degree heat (Celsius!) burning off part of the property and having a barbecue in another part. Lazy days are here again: wonderful stuff!

The nights are equally pleasant. We had a particularly dark sky two nights or so ago and it was warm enough actually to be tolerable, spending enough time outside to let one’s eyes properly adjust. I claim no credit for the following: all ToH’s doing. But I think this is pretty decent for a 4 second snapshot in the back yard one night:

What’s more surprising to me is that the picture is not a stranger to me. I mean that my eyes could see quite a lot of what that photograph shows, including the dark, ‘forked’ descending clouds in front of the central region of luminosity. I’ve seen a lot of astro-photographs where you think, ‘wow!’, but few where you think, ‘wow -and I pretty much remember it like that’.

Anyway, ToH is doing great things with a new Nikon D600. The above is merely a severely re-sized version -and saved lossily to PNG to boot. You should really see the original, but ToH’s a bit wary of letting originals out to the world like that, so you’ll have to make do with something merely illustrative of the wonders we are privileged to have on our doorstep.

In the same vein, here’s last weekend’s set of wonders:

That’s Chandler (and new Joey), still going strong, all these years later -with son-of-Boise lurking in the background, ever eager for a good time with the girls, whenever it’s available.

I have yet to master the hand-me-down Nikon D80, but with my trip to London -and Aldeburgh- fast approaching (November), I had better get some practice in.