From what I have been reading from other posts on this forum, the issue may be caused by the clear history settings. It was suppose to have been fixed in v30.

Type about:preferences#privacy<enter> in the address bar.

The button next to History, select Use Custom Settings.

At the bottom of the page, turn on Clear History When Firefox Closes. At the far right, press the Settings button. Turn on ONLY Cache and Form And Search History leaving the others off.

Hi, thank you for the respond! The issue started at me after FF46 and happens not when I click Clear Recent History... but when click Show All History and see what's in Today or last 7 Days. Because I used to clean everyday there's no that much stuff. I use this way because for some sites I need cookies deleted so use Forget That Site and for others I only delete the links so to keep cookies. Also I always leave about 10 links for my everyday surfing in few certain sites. When I'm in Show All History window and perform cleaning there then happen the Adobe Flash process and the extreme usage. I need my Form and Search History enabled and also I usually have short queues in DownThemAll addon and need to keep them too. So cleaning history when FF closes or Clear Recent History... are not useful for me. I clear the Cache via an addon. In Show All History window under History are the Downloads (usually empty), Tags and Bookmarks. The issue starts not when I just open Show All History but when start manually clearing it.

Places Maintenance {web link} Allows to run Maintenance tasks on the database that drives Places, the bookmarks and history module behind Firefox.

Open the Add-ons Manager. Locate the add-on and press the Options button. Then follow the directions.

When I had a "spinning" hard disk, "Forget About This Site" would lock up Firefox for about 60 seconds. When I switched to an SSD drive, the time dropped to barely noticeable. So I suspect there is an issue with Firefox's databases or file system being inefficiently organized, and more likely the Places database which stores history and bookmarks (when you crash Firefox, at the next startup, Firefox discards the cache, so an inefficient cache seems less likely).

Hopefully Fred's suggestion will help but, if not, you could consider removing the places.sqlite file (with Firefox closed), and letting Firefox create a new one with just your bookmarks in it.

jscher2000 said

When I had a "spinning" hard disk, "Forget About This Site" would lock up Firefox for about 60 seconds. When I switched to an SSD drive, the time dropped to barely noticeable. So I suspect there is an issue with Firefox's databases or file system being inefficiently organized, and more likely the Places database which stores history and bookmarks (when you crash Firefox, at the next startup, Firefox discards the cache, so an inefficient cache seems less likely). Hopefully Fred's suggestion will help but, if not, you could consider removing the places.sqlite file (with Firefox closed), and letting Firefox create a new one with just your bookmarks in it.

Thank you! How could I switch to SSD drive?

I read about Places Maintenance addon, seems good idea but the comments left me in a doubt. So I prefer doing this manually as you suggested with removing this file. I backed up my Bookmarks; my cookies; did FEBE and OPIE backups too, so even if something goes wrong I hopefully be able to restore everything. I had over 12 000 bookmarks before, then cleaned duplicates and now are probably around 4 500. Maybe FF keeps info about all bookmarks being in my profile.

I turned off Indexing of my system, to ease CPU usage. But might this conflict with FF databases?

Could you tell me how exactly to remove the places.sqlite file and how to let FF to make new one?

PS. I found one places.sqlite file in: user profile - AppData - Roaming - Mozilla - profiles. It is 10 MB.

Do you think it would be also good I to check for conflicting addons with Extension Conflict Troubleshooter for Firefox

After removing some 100 or so bookmark copies, I noticed there was no change in the size of the datafile. But after running the maintenance add-on, the file size was cut in half.

I have never had a problem using Places Maintenance.

FredMcD said

After removing some 100 or so bookmark copies, I noticed there was no change in the size of the datafile. But after running the maintenance add-on, the file size was cut in half. I have never had a problem using Places Maintenance.

Thank you for the info! Hope I didn't offended you about the addon, I have the habit always to read the comments. Some talk about history disappeared or bookmarks becoming a total mess (their subfolders). Any change in your profile after you using it? Cookies, history, bookmarks and their subfolders stood as they were before running Places Maintenance?

I performed Places Maintenance. The file size remained the same. I performed again with same result. According to result my database is sane.

When have history to clean later I'll see if the CPU will be as high again on Forget That Site. The annoying Adobe Flash process appears again for sure.

Hi vessto, an SSD drive is a storage device you would have to purchase. You then can use free (or free for home use) software to clone your existing hard drive to the SSD and physically switch them. I suggest searching for discussions about using an SSD drive in your specific computer to see which brands users recommend and any special issues.

Here's how you would remove the places.sqlite file, although technically the first recommended step is a bookmark backup.

(1) Create an extra bookmark backup using the steps in this article: Restore bookmarks from backup or move them to another computer.

(2) Open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" button > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Show Folder" button. This should launch a new window listing various files and folders in Windows Explorer.

Leaving that window open, switch back to Firefox and Exit, either:

• "3-bar" menu button > "power" button
• (menu bar) File > Exit

(3) Pause while Firefox finishes its cleanup -- give it a good 15-30 seconds -- then rename places.sqlite to something like places.old. The reason for renaming rather than deleting is in case Firefox is not able to restore your bookmark backup.

If you see other similarly named files like places.sqlite-shm and/or places.sqlite-wal, you can delete those.

(4) Start Firefox back up again. When it fails to find places.sqlite, Firefox should create a new one and restore your bookmarks from your last automatic backup.

Are the bookmarks complete? If not, you can restore you manual backup using the steps in the above article.

So SSD is something like RAID where a same info is stored in two servers and thus is safe and they have less usages?

Thank you! I need to think a bit before performing that important step. I'll backup bookmarks but what will happen with cookies, history and addons (and most of mine are customized).

While seeing the size of my places.sqlite I saw similarly named files, can I freely manually delete them from the folder?

I saw three files named ffmpeg, with same size, is it normal?

Places Maintenance again didn't lessen the size of the file after vacuuming and said database is sane. Maybe I just have too many bookmarks (probably 6 000 as I saw during the maintenance). Or there's conflict between manually cleaning and some addon.

These can't get your data back, but will help in the future.

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backups of files that you choose.

OPIE {web link} Import/Export extension preferences

vessto said

So SSD is something like RAID where a same info is stored in two servers and thus is safe and they have less usages?

No, SSD is a semiconductor memory device that emulates a hard drive. There is no redundancy.

While seeing the size of my places.sqlite I saw similarly named files, can I freely manually delete them from the folder?

Only the two files I mentioned.

I saw three files named ffmpeg, with same size, is it normal?

I don't know what those files are. If you have any video downloading extensions, they might use ffmpeg to convert between formats.

Places Maintenance again didn't lessen the size of the file after vacuuming and said database is sane. Maybe I just have too many bookmarks (probably 6 000 as I saw during the maintenance). Or there's conflict between manually cleaning and some addon.

The SQLite database component might not release disk space to Windows after internally reorganizing the database. Pre-allocating space to a database file speeds up disk writes. However, I'm not familiar with the details of what is the preferred minimum size.

FredMcD said

These can't get your data back, but will help in the future. These add-ons can be a great help by backing up and restoring Firefox FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backups of files that you choose. OPIE {web link} Import/Export extension preferences

Thank you, I have them. I said above I made backup with both soon. I never restored from OPIE but I think I restored with FEBE once or twice and it gave back everything, including history and cookies. I have set FEBE to backup everything possible. Also I backup the cookies with Advanced Cookies Manager.

jscher2000 said

vessto said

So SSD is something like RAID where a same info is stored in two servers and thus is safe and they have less usages?

No, SSD is a semiconductor memory device that emulates a hard drive. There is no redundancy.

While seeing the size of my places.sqlite I saw similarly named files, can I freely manually delete them from the folder?

Only the two files I mentioned.

I saw three files named ffmpeg, with same size, is it normal?

I don't know what those files are. If you have any video downloading extensions, they might use ffmpeg to convert between formats.

Places Maintenance again didn't lessen the size of the file after vacuuming and said database is sane. Maybe I just have too many bookmarks (probably 6 000 as I saw during the maintenance). Or there's conflict between manually cleaning and some addon.

The SQLite database component might not release disk space to Windows after internally reorganizing the database. Pre-allocating space to a database file speeds up disk writes. However, I'm not familiar with the details of what is the preferred minimum size.

Now I guess one of my video downloaders uses ffmpeg to decode after downloading.

I noticed content-prefs.sqlite is 509 MB! According this article it is caused from zooming images and I have Image Zoomer addon which I use often. Also I download and upload much, in many different locations. According the same article I can just delete content-prefs.sqlite and then just reopen FF and it will make new file. I won't lose anything important as it contains only download/upload locations. If this is correct and I can safely delete or zip it I'll do it.

SSDs seems expensive here, and the biggest is 256 GB and I have 1 TB HD and 1 TB + 320 GB in two External drives.

I don't know everything stored in content-prefs.sqlite, but generally speaking, it would be site-specific information other than permissions (e.g., cookie/popup permissions).

I bought a 500GB SSD (Samsung EVO) for a laptop from Amazon. I see the 1TB size is about $312 (http://www.amazon.com/Samsung-2-5-Inc.../B00OBRE5UE). Maybe you don't need your C drive to be that large?

jscher2000 said

I don't know everything stored in content-prefs.sqlite, but generally speaking, it would be site-specific information other than permissions (e.g., cookie/popup permissions). I bought a 500GB SSD (Samsung EVO) for a laptop from Amazon. I see the 1TB size is about $312 (http://www.amazon.com/Samsung-2-5-Inc.../B00OBRE5UE). Maybe you don't need your C drive to be that large?

I asked in the article about this file and also tomorrow will read it again on clear brain. If content-prefs.sqlite doesn't contain anything imporant will first rename and if everything is ok with FF then move it on my GDrive if needed to be back someday.

I did partition when I got the PC. Left 120 GB for C and 780 for the other. 100 GB seems reserved for system stuff. My pagefile is 6 GB min and max (1.5x original RAM) and is located on C.

$300 is too expensive for me.:( This was my salary when I worked and I'm unemployed now.

I renamed content-prefs.sqlite and FF made new one, with the default 224 KB size. I saw all my cookies, extensions, bookmarks and history are here, as must be as content-prefs.sqlite doesn't contain them. Then I zipped and moved the file. Tried to clean history manually (including Forget About This Site) with and CPU was about 2-3%, not 90. Maybe this was the solution as places.sqlite is neither big nor is corrupt according to Places Maintenance. Will see this evening too, in the next manually history cleaning, if CPU is normal again I'll probably accept this as being the solution.

I tried to clena history again with many sites to delete, most of them with Forget That Site. CPU was absolutely normal. That is why I marked my own reply above as a solution.

Bonus is the CPU usage during surfing also seems affected and now is normal *knocks on wood*, not that 50-60% when opened 2-3 tabs. I wish I'd suggest FF developers to include content-prefs.sqlite info in their articles about how to lessen CPU usage in Mozilla.

That was very good work. Well Done.

FredMcD said

That was very good work. Well Done.

Thank you! I'm so grateful to you and jscher2000 for all tips!