[Morf]

Hmmm,

I've just restarted my Kindle twice, once from the menu (Settings...Menu...Restart) and once with the holding the power switch until your finger hurts ( ), and although I see the effect of the books not appearing for a couple of seconds (the collections all show 0 books for a moment), I saw no signs of it re-indexing, I carried out NogDog's tests and got the same results.

So I suspect it's actually only a reset to factory defaults which wipes the index, and I'm not going to test that for obvious reasons! 

 

[Morf]

Morf, unless you've done a search for a dummy phrase, you might not "see the effects" of re-indexing.

When I said I tried NogDog tests, I meant this:

...immediately tried two searches from the home screen: first for a nonsense "word", which returned no matches and no indication that it could not search any items (which you normally get for any item which is still being indexed); and then the second search for a "real" word, which was successfully found in a bunch of my books.

So yes, I did do a nonsense search, and no, I did not get an error just "No Items". I've just repeated the test with the same results.

I stand by my test: on my Kindle 3 (UK 3G, B00A serial number, running V3.1) a restart does not apparently cause reindexing (unless, as NogDog says, it finishes in seconds, and there are 200 books in there so I doubt that).

That doesn't mean to say that this applies to all machines in all circumstances: as I understand it (http://en.wikipedia.org/wiki/Amazon_Kindle) there have been two versions of the DX, the older white one (B004 serial number) and the newer graphite one (B009), and neither have the same OS version as the Kindle 3 so either or both may behave differently.

...I've not had this happen on the new DX, but I speak from experience on my old one where I had this happen a few times. And I know it was re-indexing because I did the search.

Were they different versions - was the old one a B004 and the new one a B009? It may be that Amazon have changed this behaviour in the newer OS.

If other people want to do the same test (after all, it's not as if a restart causes any harm) and report their results and version numbers we might be able to pin down the exact circumstances in which reindexing does and doesn't happen.

 

[Morf]

brillig isn't a good word to use for this test, because it does appear in a book (assuming you've got Alice on there!). You need to search for something completely random, I just rub my thumb straight over the middle of the keyboard and so get a truly nonsense word.

Remember that brillig may be nonsense to you, but it's a word to the Kindle because it appears in a book.

The way indexing works, if the word isn't in the index, it will report back very quickly that this is the case. If it is in the index, it then has a lot more work to do, because it has to do a lookup from the index to find the word in the books where it appears, then it has to open the book and look up the word, then it has to pull the location out of the book and display it. This all takes time.

I suspect that it caches the search results, so if you do the search again straight away, it will have the answers already to hand.

No idea why slithy was quicker, maybe it's a woody word and brillig is a tinny word! (Monty Python, http://orangecow.org/pythonet/sketches/woodytin.htm)

 

[Morf]

Even if the word is found, the Kindle will display the number of unindexed items if any items are unindexed.

Ah, I didn't realise that, I've never had the "unindexed items" problem, so I was just going on what I had read elsewhere. Apologies for the confusion!

What I found interesting was that a search for an indexed word was faster after doing a search for a non-indexed non-word.
...
I suspect that the index might be loaded into memory.

This could indeed be the correct analysis.