Why is my Kobo Clara BW slow in loading books (8-15secs)?

[cakepuller]

Why is my Kobo Clara BW slow in loading books (8-15secs)?

I just got my Kobo Clara BW yesterday and have been playing around with it.

I found that when I tap a book (all books sideloaded from Calibre 7.11) on HOME or MY BOOKS, it takes at least 8 seconds to appear. If it is a book that I have not tapped on before, it takes about 15 seconds. I.e: first time tapping = 15 seconds; subsequent times=8 seconds.

In comparison, my very old Kobo Aura takes under a second to load the book when tapped.

I tried books of varying sizes, all with the same result as described.

At first I thought it could be a timeout issue, so I poked around the SETTINGS to turn off anything that could suggest contacting the internet. Turned off AUTO SYNC and AUTOMATICALLY SHARE DATA.... But this didn't change anything. Still slow book loading.

I usually turn off wifi (to save power), so I thought maybe turning wifi on might speed things. Nope, it didn't.

Everything else is fast - page turns, search, sorting, marking as read,

Although, adjusting fonts/margins/spacing... within a book is also unexpectedly slow. At least 4 times slower than my Aura.

So, is this fixable?
Is anyone else seeing this?

It's annoying. Especially when I want to go through several books quickly to, say, see the page covers, for example.

[user105]

Same thing on the tolino shine 5, which has the same hardware.
I got it briefly fixed by going to devmodeon and switch render to rmsdk
Sadly kobo removed the devmode with the 8115 update

I am curious to hear other people’s experiences, since I thought this error is exclusive to the tolino 5.0 fw and in YouTube reviews, books are opened immediately

[.tycho]

Are you sideloading as EPUB or KEPUB? Latest firmware installed?

If everything is backed up in Calibre, what if you try a factory reset and try again?

[user105]

At least for me it’s a full yes.

I ordered the kobo version now , too to see if that works for me better. But reading this post makes me worried ; for some units having a faulty cpu or just bugged libraries.

If op did not do anything weird, there are units of the same hardware, running different os versions with the same bug. Nothing too strange but I am hoping this can be fixed via software


And I don’t even think it’s cpu related. Otherwise why would rmsdk load in an instant ?

And epub and keeping load at the same slow speed for all books.

But if identical software causes different behaviour, it seems like hardware problem.

Or a pcb difference due to different suppliers

[cakepuller]

.....
Edit: Sorry I deleted my original text here 'cause I realised it was wrong. See my followup post below.

[patrik]

If you buy a book from Kobo (there are plenty of free ones to test with), does that also open as slowly?

[cakepuller]

Originally Posted by patrik

If you buy a book from Kobo (there are plenty of free ones to test with), does that also open as slowly?

@patrick

Wow, that was an excellent suggestion for an experiment. I went to Kobo and "bought" a free book and it opened under 1 second on my Clara BW! I tested further and indeed kepub's do open much faster than regular epub. Changing the book's fontsize/margins/font was also much faster with kepub!

Thank you @Patrick and @tycho.

I guess this means I'll have to convert to kepub from now on before sideloading to the Clara BW.

Does this mean Kobo will not be fixing the slowness of opening regular epubs?

[JSWolf]

Try a reboot and then see how fast your eBooks open.

[user105]

This makes me again wondering what i am doing wrong.

Would someone please be so kind to supply a scrambled or free kepub.epub file for me to test again?
For kepub created by the extended driver is a he load time identical to epubs and the test files I created on https://pgaskin.net/kepubify/try/ is either not loading for the same speed

[Quoth]

I used to use kepub, but only use epub now. No slow opening on Libra, Libra2, Sage or Elipsa of epub.

[Quoth]

Originally Posted by user105

This makes me again wondering what i am doing wrong.

Do you have huge covers?
What difference does it make if you page in a bit, go back to My Books and re-open same epub?

[rcentros]

Originally Posted by cakepuller

Does this mean Kobo will not be fixing the slowness of opening regular epubs?

I sure hope not. I almost exclusively read ePubs, not KePubs on my Kobos.

[cakepuller]

Originally Posted by JSWolf

Try a reboot and then see how fast your eBooks open.

I just tried this. No change. Still slow 9-second opening of EPUBs, but under one second for KEPUBs.

[JSWolf]

Originally Posted by cakepuller

I just tried this. No change. Still slow 9-second opening of EPUBs, but under one second for KEPUBs.

You never did answer the question. Do you have some very large covers? I take large covers and large titlepages and reduce them down to 1680 lines. I also lossless recompress all the graphics using a level of 70 for the compression. Yes, it's a lossy compression but after that's done, the losless part removes all the excess data in the graphics files.

[John F]

Originally Posted by JSWolf

... I also lossless recompress all the graphics using a level of 70 for the compression. Yes, it's a lossy compression but after that's done, the losless part removes all the excess data in the graphics files.

Just to clarify for me, you are saying you do a lossy compression of level 70, and then do a lossless compression, or do you do a lossless compression and then a lossy compression of level 70? (I don't know if there is difference in the file size if the order is different.)