Viewer slow first read and what are the shortcuts - Page 4

kovidgoyal · 05-03-2021, 12:12 AM

Quote:

Originally Posted by Geremia

I notice that when ebook-reader is open, the graphics (such as switching virtual desktops) really slows down. I don't have these issues with any other apps.

As I said right at the beginning you have graphics driver issues.

Quote:

Also, ebook-viewer run stand-alone from the commandline is much faster at loading books than ebook-viewer launched from within Calibre by hitting "v" key. "Loading book, please wait" takes less than a few seconds, compared to several seconds.

I dont see how thats possible since they run the exact same code and indeed I cannot replicate it on my linux system.

jbacelar · 05-03-2021, 06:00 AM

Geremia · 05-06-2021, 08:17 PM

Quote:

Originally Posted by kovidgoyal

you have graphics driver issues.

maybe

Code:

            megapixels        bridge ready (seconds)
640x480     	0.31	3.34
720x480     	0.35	3.36
800x600     	0.48	3.32
1024x768    	0.79	0.79
1280x720    	0.92	0.84
1152x864    	1.00	0.71
1280x800    	1.02	3.46
1280x1024   	1.31	3.34
1600x900    	1.44	3.24
1600x900    	1.44	3.38
1920x1080   	2.07	3.42
2560x1440   	3.69	2.98
3840x2160   	8.29	16.64

I wonder why 3840x2160 is such an outlier.

kovidgoyal · 05-06-2021, 09:40 PM

If I had to guess it would be because there isnt enough VRAM on your GPU for that resolution. This will cause the equivalent of swap thrashing for the GPU, as the driver has to keep moving things from GPU memory back nd forth to system memory.

Geremia · 05-07-2021, 05:51 PM

Quote:

Originally Posted by kovidgoyal

If I had to guess it would be because there isnt enough VRAM on your GPU for that resolution. This will cause the equivalent of swap thrashing for the GPU, as the driver has to keep moving things from GPU memory back nd forth to system memory.

Maybe. VRAM usage goes from 588 MB (60%) to 891 MB (91%) after opening ebook-viewer.

Geremia · 09-13-2021, 06:58 PM

Quote:

Originally Posted by kovidgoyal

If I had to guess it would be because there isnt enough VRAM on your GPU for that resolution.

I bought a new graphics card with 8GB of VRAM, and ebook-viewer doesn't start any faster: 3840x2160 takes about 7 seconds, but lower resolutions take <1 sec. I'm using Nvidia's proprietary driver.

WHY · 09-17-2021, 03:09 PM

I had the same issue and found that Library Maintenance > Check Library helps! At least it works for me. Whenever it becomes slow again after I add more books, I just need to repeat the above process and then the new book openning will become much quicker afterwards

BetterRed · 09-17-2021, 06:23 PM

Quote:

Originally Posted by WHY

I had the same issue and found that Library Maintenance > Check Library helps! At least it works for me. Whenever it becomes slow again after I add more books, I just need to repeat the above process and then the new book openning will become much quicker afterwards

that's weird

Check Library 'cleans' the library database and checks to see if the library database content is in synch with the library author and book folders and format files.

The viewer is a separate executable (ebook-viewer.exe) that doesn't need a library, e.g. I can run it and open a book format file that's on my desktop, in my downloads folder etc.

I don't understand why removing 'crud' from a calibre library database should have any impact on the performance of the viewer.

BR

theducks · 09-17-2021, 08:15 PM

Quote:

Originally Posted by BetterRed

that's weird

Check Library 'cleans' the library database and checks to see if the library database content is in synch with the library author and book folders and format files.

The viewer is a separate executable (ebook-viewer.exe) that doesn't need a library, e.g. I can run it and open a book format file that's on my desktop, in my downloads folder etc.

I don't understand why removing 'crud' from a calibre library database should have any impact on the performance of the viewer.

BR

Agreed. Does not compute! The DB is not directly involved once the selection is made.
Loading the book always seems to take time (even on a fast machine). Once loaded, things are snappy.

WHY · 09-17-2021, 10:33 PM

Quote:

Originally Posted by theducks

Agreed. Does not compute! The DB is not directly involved once the selection is made.
Loading the book always seems to take time (even on a fast machine). Once loaded, things are snappy.

I have no idea at all about how calibre works in the background. By the way, just curious, does this trick works for you guys?

theducks · 09-17-2021, 11:25 PM

Quote:

Originally Posted by WHY

I have no idea at all about how calibre works in the background. By the way, just curious, does this trick works for you guys?

No! I run phase 1 of the tool about 2 times a month.
FWIW I think Calibre starts up faster (GUI usable) than the Viewer (Book usable) on my main machine.

BetterRed · 09-18-2021, 07:15 AM

Quote:

Originally Posted by WHY

I have no idea at all about how calibre works in the background. By the way, just curious, does this trick works for you guys?

Not to me, but I haven't noticed any degradation in viewer performance over time.

If you are viewing ePubs, then next time it slows down try opening the epub directly via file manager open with before you run a library check.

BR

WHY · 09-18-2021, 11:41 AM

Quote:

Originally Posted by BetterRed

Not to me, but I haven't noticed any degradation in viewer performance over time.

If you are viewing ePubs, then next time it slows down try opening the epub directly via file manager open with before you run a library check.

BR

Yes, if open the epub file directly from the file browser, it would be quick with no issue. The odd things is that opening a new book within calibre can be very slow and the library check can resolve this issue for me for the reason I don't know..

theducks · 09-18-2021, 12:30 PM

Quote:

Originally Posted by WHY

Yes, if open the epub file directly from the file browser, it would be quick with no issue. The odd things is that opening a new book within calibre can be very slow and the library check can resolve this issue for me for the reason I don't know..

Can you narrow down the 'slow' phase?
1)time from when you click View (or type V)
2)time from when viewer shows 'Preparing' to text appears?

WHY · 09-18-2021, 01:25 PM

[QUOTE=theducks;4155207]Can you narrow down the 'slow' phase?
1)time from when you click View (or type V)
2)time from when viewer shows 'Preparing' to text appears?[/QUOTE

1) Less than 1 sec
2) As I don't have the slow issue now, for this phase it takes less than 3 sec typically. To my memory, if it is slow, then it might take 20 sec or even longer for this phase.

05-03-2021, 06:00 AM	#47
jbacelar Interested in the matter Posts: 421 Karma: 426094 Join Date: Dec 2011 Location: Spain, south coast Device: Pocketbook InkPad 3	Last edited by jbacelar; 05-03-2021 at 06:05 AM. Reason: An oversight.

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05-06-2021, 09:40 PM	#49
kovidgoyal creator of calibre Posts: 44,542 Karma: 24495948 Join Date: Oct 2006 Location: Mumbai, India Device: Various	If I had to guess it would be because there isnt enough VRAM on your GPU for that resolution. This will cause the equivalent of swap thrashing for the GPU, as the driver has to keep moving things from GPU memory back nd forth to system memory.

09-17-2021, 03:09 PM	#52
WHY Enthusiast Posts: 33 Karma: 10 Join Date: Mar 2021 Device: none	I had the same issue and found that Library Maintenance > Check Library helps! At least it works for me. Whenever it becomes slow again after I add more books, I just need to repeat the above process and then the new book openning will become much quicker afterwards

09-18-2021, 01:25 PM	#60
WHY Enthusiast Posts: 33 Karma: 10 Join Date: Mar 2021 Device: none	[QUOTE=theducks;4155207]Can you narrow down the 'slow' phase? 1)time from when you click View (or type V) 2)time from when viewer shows 'Preparing' to text appears?[/QUOTE 1) Less than 1 sec 2) As I don't have the slow issue now, for this phase it takes less than 3 sec typically. To my memory, if it is slow, then it might take 20 sec or even longer for this phase.

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