Ghost apps? Symbolic views that just won't go away.

[TheLastMillennial]

Hi, I'm having an issue where sometimes deleted apps just decide to leave behind a 'symbolic view' that never goes away no matter how many times I delete it or reset my Prime. The issue is specifically a problem with deleted PDFs and Flappy Bird. All of which I deleted several months ago but their symbolic views keep popping back up in the apps menu every couple days. I'm currently running the latest beta on my G2, however this was also an issue on the previous OS.

I'd appreciate it if someone could explain what's going on and how I can permanently get rid of the apps!

[Joe Horn]

G2 machines (HW rev D) have been exhibiting this behavior for over a year now, and still are, with beta FW rev 14284 installed. Example:

(1) Save any app using any name you like.
(2) Toggle power, to save everything to flash.
(3) Delete the copied app you saved.
(4) Toggle power, to ensure no RAM ghosts are present.
(5) Perform an On+Symb warmstart (or a paperclip warmstart).
--> Your saved app will reappear (as well as all previously deleted apps).

This does not seem to happen with G1 machines (HW rev A or C) with the most recent beta FW installed (rev 14298).

Hmm... I just noticed that G2 machines revive these ghost apps not only by warmstarts, but even by putting the G2 into coma mode by pressing Shift down, holding it down, and pressing On for one full second before releasing both. When the G2 reawakens from coma mode (it takes a few seconds after pressing On), the ghost apps will have reappeared. The OP's experience seems to indicate that this can happen even if the coma mode was initiated by the calculator itself (which it does after several days of inactivity).

Any other insights regarding this phenomenon of ghost apps would be greatly appreciated.

[TheLastMillennial]

*bump* Is there any more information people would like to add? Joe Horn's steps perfectly reproduced my issue. Is a bug fix being looked into?

EDIT: Thanks Tim!

[Tim Wessman]

I have it captured. Seemed like might be a filesystem caching thing going on possibly???

[Username]

Hello,
there are any new information about this problem? (I have the same problem) :-(

Username

[TheLastMillennial]

Yes, I'd love to hear if this bug is fixed in the next OS or if there's any new news. I'm still experiencing it as well.

[cyrille de brébisson]

Hello,

I can confirm that the problem lies in the file system, but I never managed to find the root cause.

Updating to a later version of the FS might help...
I will give it a try.

Cyrille

[medwatt]

(06-24-2020 05:56 AM)cyrille de brébisson Wrote:  Hello,

I can confirm that the problem lies in the file system, but I never managed to find the root cause.

Updating to a later version of the FS might help...
I will give it a try.

Cyrille

And the bug that I reported almost 6 months ago regarding the Prime not booting up from a restart when the Control app is installed ?

[cyrille de brébisson]

Hello,

Sorry, I never looked at it.
Can you send me a link to said app and I promis I will look at it this week (or early next week).

Cyrille

[BERNARD MICHAUD]

Until a permanent solution is found re: Ghost apps you can perform a Factory RESET if you wish. The instructions below appear to be lengthy, but the process is fairly quick.

1- Connect your Calc. to your PC via (USB) and link to your Connectivity Kit (CK).
2- In the CK, open the blue Content folder and Backup all Programs and Apps you wish to keep. No need to delete any ghost Apps.
3- Turn your Calc off and disconnect (USB) from the PC.
4- Hold your Calc securely with your THUMB and PINKY finger while pressing and holding the three keys F C O with your Ring, Middle and Index fingers. It is very important that you do not let go of any of the three F C O keys until the process is over.
5- Turn Calc sideways and push a paper clip into the RESET hole at the back of the Calc then release the clip and wait until the screen lights up before you release the three F C O keys.

At this point the EA656 DIAGNOSTIC screen will be displayed.
1-Press 4. FLS Utility. The screen will change to FLASH UTILITY.
2-Press 3 to highlight 3. Format Disk C followed by [Enter] and wait until the screen returns to FLASH UTILITY.
3-Press [ESC] to return to EA656 DIAGNOSTIC screen.
4-Press C. POWER OFF MODE (NOT 9. RESET) to exit EA656 DIAGNOSTIC.
5- Link back to your CK via (USB) and re-INSTALL the Programs and Apps you previously backed up.

BM

[pinkman]

From a computer point of view, this looks like the Master Boot Records describing the deleted (ghost) App are not cleared.
The primitives of deletion of the G2 filesystem are probably buggy.

[BERNARD MICHAUD]

(06-25-2020 05:49 PM)pinkman Wrote:  From a computer point of view, this looks like the Master Boot Records describing the deleted (ghost) App are not cleared.
The primitives of deletion of the G2 filesystem are probably buggy.

The procedure described above simply allows you to invoke the Dyagnostic Window where you can then select option 4 which will re-format drive C which contains user-generated Apps and Programs and returns the calculator to it original Factory condition. You can then reinstate your needed Apps and Programs which you backed up before the procedure.

Naturally if you delete Apps again, thereby re-creating annoying Ghost App before a permanent solution is found by HP concerning Ghost Apps removal, you can use the procedure I described above to get rid of them once more. User Apps and Program reside on the C drive.

BM

[medwatt]

(06-25-2020 04:40 AM)cyrille de brébisson Wrote:  Hello,

Sorry, I never looked at it.
Can you send me a link to said app and I promis I will look at it this week (or early next week).

Cyrille

Here is the app: https://www.hpmuseum.org/forum/thread-11597.html

Here is the post where I explained what is happening: https://www.hpmuseum.org/forum/thread-14...#pid125755

[cyrille de brébisson]

Hello,

>From a computer point of view, this looks like the Master Boot Records describing the deleted (ghost) App are not cleared.
>The primitives of deletion of the G2 filesystem are probably buggy.

Except that this is not how flash file system works.
On a old style hard drive a section of the drive was dedicated to the master index.
One issue with this is that this single location on the drive (actually 2 as they was a copy) gets written/erased all the time.
The problem is that flash has a limited number of write cycles. So, should you use that type of system, you would soon wear out that sector and then would end up SOL...
So, most flash are organized as a "sequential"/"logging" file system.
Here, there is NO master table. You write a file, and then, later, if you erase is, you write the fact that you erased it... writing sequentially in the flash, and not going back.
At boot time, you are supposed to re-read said log and recreate your file system tables and the like...
Prime uses YAFFS (Yet Another Flash File System) to do this...
But I guess something is wrong somewhere, but I do not know where...

Cyrille

[pinkman]

Thanks for keeping me up to date. I was born in floppies and HDD!

I spend a few minutes on googling if there was known issues with ghost files in YAFFS, and did not find something relevant (only this thread of 2011).
If the primitives where buggy there would have been questions on the support mailing list of YAFFS, but I could not find any.
On the other hand, it is necessarily at a low level, otherwise the files would not reappear only after reboot (when the filesystem is parsed). The fact that a format C is the only (known) way to suppress them is another clue for a low level bug.
But I’m puzzled by the fact that a backup, according to Bernard Michaud’s post, doesn’t seem to “see” those files.

Please note: I’m only trying to wonder about what could happen here, from a black box point of view, and I do it aloud, you can ignore my blind tries of investigation!

[ijabbott]

Possibly, it's powering down the flash before pending writes have completed?

[BERNARD MICHAUD]

(06-27-2020 07:54 AM)pinkman Wrote:  But I’m puzzled by the fact that a backup, according to Bernard Michaud’s post, doesn’t seem to “see” those files.

2- In the CK, open the blue Content folder and Backup all Programs and Apps you wish to keep. No need to delete any ghost Apps.

A clarification of the above sentence. Perhaps I should not have used the word BACKUP but rather copy/paste all Apps and Programs you wish to keep. In fact, if you already had all those Apps and Programs in your CONTENT folder, you could have ignored step 2 altogether. After Formatting the C memory, you simply had to paste your Programs and Apps back into your calculator. I understand that if you do an actual BACKUP/RESTORE your Ghost files are still there and they would be restored as well, which would defeat the whole purpose.
Sorry if I misled anyone!

BM

[pinkman]

(06-27-2020 08:27 PM)ijabbott Wrote:  Possibly, it's powering down the flash before pending writes have completed?

According to YAFFS documentions, the system does not entirely rely on background operations: when you ask for a deletion, it first synchronously marks them as removable, and then the garbage collector is called to convert from removable to empty.
If you turn the power off before the garbage collection, the system will execute it after the next reboot and access to the FS. If you turn off before the removable flag has been set, then there is no deletion at all.

[pinkman]

Thank you Bernard for the details, it confirms my intuition!that it is at a low level: something in YAFFS or between YAFFS and the Prime OS is going wrong.

[CyberAngel]

(06-26-2020 05:03 AM)cyrille de brébisson Wrote:  Hello,

>From a computer point of view, this looks like the Master Boot Records describing the deleted (ghost) App are not cleared.
>The primitives of deletion of the G2 filesystem are probably buggy.

X
Prime uses YAFFS (Yet Another Flash File System) to do this...
But I guess something is wrong somewhere, but I do not know where...

Cyrille

No bug. The delete was never written to the log.
OR
one bit turned wrong (happens 1:million on any system w/o EEC etc)

Trust the underlying OS - it is Chinese quality work.
- -
VP