hi, firefox doesn't store an unlimited amount of history entries but calculates a maximal number it can handle performance wise on a system.

you could try to adjust (increase) this number manually on your own risk: enter about:config into the firefox address bar (confirm the info message in case it shows up) & search for the preference named places.history.expiration.transient_current_max_pages. double-click it and change its value to a higher number...

Thanks for your help! The value for this parameter was 104858. When I double click it, it does becomes highlighted, but when I type a new value, the updated value is not stored. I checked that I was able to modify the values for other parameters, but not places.history.expiration.transient_current_max_pages.

oh you're right - i can't get it to work either, it must have been a long time since i last tried that...

How long does it take to reach this calculated maximum (how many months do you keep)?

places.history.expiration.transient_current_max_pages is a read-only pref that reflects the calculates value, so changes made to this pref won't have any effect.

You can create a new integer pref named places.history.expiration.max_pages if you want to adjust the automatically calculates number of pages to keep. Be cautious with setting the value of this pref. Note that you can do a copy and paste of history items to a bookmarks folder.

See:

• http://bonardo.net/mozilla/2012/02/13/places-got-async-expiration.html

Thanks! I am trying your suggestion.

I will add that the number of pages stored was apparently only about half of my value for places.history.expiration.transient_current_max_pages.

To minimize storage I cleared many entries from sites where various actions create a new History entry such as Google Maps. Also I am exporting History in a simple way by placing items in a Bookmarks folder and using Export Bookmarks…

Note that the space for History is shared in a database of bookmarks with bookmarks taking precedence, so the more bookmarks you have the less History will be stored, at least up to certain limit.

There is an addon that tries to repair that database, and one option it has is to generate a short text file as a summary of the database status.

You could install and run that addon and see if its repair options help and also copy and paste its log into your reply.

• Places Maintenance: https://addons.mozilla.org/firefox/addon/places-maintenance/

This is part of the report from one of my profiles

History can store a maximum of 60100 unique pages
Table moz_places has 12240 records
Table moz_historyvisits has 20878 records
Table moz_inputhistory has 299 records
Table moz_hosts has 657 records
Table moz_bookmarks has 2501 records 

That has

places.history.expiration.transient_current_max_pages;60100

So in thousands 2.5 bookmarks, 60 spaces 21 History visits. So I have tens of thousand of spaces left for more bookmarks or History.

Thanks for the useful info! The report below reflects the change I made as per a suggestion in a preceding reply.

History can store a maximum of 216000 unique pages

Table moz_places has 95774 records Table moz_historyvisits has 148621 records Table moz_inputhistory has 138 records Table moz_bookmarks has 5743 records

I note that moz_historyvisits has a value higher than my former places.history.expiration.transient_current_max_pages value – does this mean the History is still stored but not displayed? Would it be possible to restore the History (to the usual display) that was cleared because of the places.history.expiration.transient_current_max_pages.value?

The cleared history will have been cleared on a rolling basis. The maximum number of entries will have stayed roughly the same. Thee will be no large tranche of history entries to find and recover.

You will now be able to use a larger maximum. You probably can not get back deleted items. I suppose hypothetically you could try recovering older versions of places.sqlite and see if there is some way to stitch them together using a sqlite editor but although I have examined places.sqlite and extracted information, I have never contemplated such an operation. Look at the old structure of the database in this /questions/1113896#answer-855151 and the expiry code for anyone who understands it http://mxr.mozilla.org/mozilla-central/source/toolkit/components/places/nsPlacesExpiration.js <-- The remarks are often useful as an indication of what is happening.

Ben_709 said

I note that moz_historyvisits has a value higher than my former places.history.expiration.transient_current_max_pages value – does this mean the History is still stored but not displayed?

Some of those visits probably were to the identical URL (Firefox only displays the latest visit to a URL but it store information on earlier ones). I think the maximum page number is more closely related to the number of records in moz_places.