Question about memory

[cybmole]

good to have a technical explanation but that seems to be poor design.

If I read you correctly, and I have let's say 999 books installed on any? kindle, then I connect via usb and add just 1 more book, it's then going to check the indexing of the original 999 as well as index the new one.

is that scenario only applicable with usb- let's say I have the same 999 installed books and I now add one new one via wi-fi from amazon cloud or from amazon store, does that then skip all that additional validation ?

[eschwartz]

Originally Posted by NullNix

I doubt that -- indexing is largely dominated by the CPU overhead of decompressing ebook pages and the power overhead of writing the resulting indexes (writing is much more power-expensive than reading).

The principal cause of a slowdown with a large number of books is that whenever you turn the Kindle on after plugging it into USB, well, the indexes are on the USB-accessible portion of the filesystem, so on first powerup after unplug it has to assume they're potentially corrupted and revalidate them, which involves reading most pages of the indexes, though not the ebooks themselves. If, like me, you have 150 megabytes of indexes, this can take half an hour or more of 100% CPU usage, and drain a significant fraction of the battery.

Why do you think the Kindle does integrity checks on remounting the userstore?
I've never noticed that slowdown...

(I also can't help but wonder if my PW1 is failing to remove some indexes when books are removed. 150MiB of indexes for 600MiB of books seems like an awful lot! Maybe I should vape the oldest and let it recompute any that seem necessary, but I'm not sure if the Kindle will realize it has to reindex if I do that, and unlike the original poster I use those indexes quite heavily.)

I am pretty sure the Kindle can clear up old indexes on its own. But if you manually delete them all, it will definitely re-index from what I remember.

[HarryT]

Originally Posted by cybmole

good to have a technical explanation but that seems to be poor design.

If I read you correctly, and I have let's say 999 books installed on any? kindle, then I connect via usb and add just 1 more book, it's then going to check the indexing of the original 999 as well as index the new one.

No, it definitely does not do this. Indexing activity only occurs when you add a new book.

[jbcohen]

Memory is not normally subject to slowdowns in retrieval no matter how old the unit is I would be more inclined to think it's the CPU. I would recommend a new unit.

[GA Russell]

OK, here's the situation.

I did what Harry instructed in post #13, and the screen eventually said, "Search Results: All 0 Items

No Items"

So I guess everything was indexed.

I think that during all of this I accidentally rebooted the unit. So we'll see if there is a noticeable difference in the performance.

[NullNix]

Why do you think the Kindle does integrity checks on remounting the userstore?

You can see it doing it if you've jailbroken and installed usbnetwork: do a ps upon remount and you'll see a process whose name I forget pounding away, 100% CPU usage. Check what files it's opening, and look, it's opening every index in turn and flicking through it. (Well, OK, I didn't check that. But it's opening a lot of indexes and walking through each fairly linearly.)