I have several versions of SQL Server, used for testing, installed on my laptop (2012, 2014, 2016, and 2017). I noticed the other day that there was a folder containing prior versions of files across updates (SPs, CUs). Across all versions there is actually quite a bit of space being taken up:
(in C:\Program Files (x86)\Microsoft SQL Server\)
110\Setup Bootstrap\Log - 91.8 MB (818 files) 110\Setup Bootstrap\Update Cache - 608 MB (2,382 files)
(all folders below reside within: C:\Program Files\Microsoft SQL Server\ )
110\Setup Bootstrap\Log - 1.18 GB (3,715 files) 110\Setup Bootstrap\Update Cache - 9.58 GB (14,766 files) 120\Setup Bootstrap\Log - 569 MB (2,963 files) 120\Setup Bootstrap\Update Cache - 5.74 GB (12,797 files) 130\Setup Bootstrap\Log - 448 MB (2,808 files) 130\Setup Bootstrap\Update Cache - 3.84 GB (8,579 files) 140\Setup Bootstrap\Log - 84.3 MB (687 files) 140\Setup Bootstrap\Update Cache - 937 MB (1,571 Files)
Totals for those folders are (MB have been normalized to GB):
Folder GB Files ---------- ----- ------ Log 2.35 10,991 Update Cache 20.66 40,095 TOTAL 23.01 51,086
Initially I figured that it should be safe to remove the Log and Update Cache folders, but then I reckoned it best to first check to see if others have asked this and if so, what the answer(s) had been. I found this KB article:
What happens if you remove this folder or delete its contents?
If the Update Cache folder or some patches are removed from this folder, you can no longer uninstall an update to your SQL Server instance and then revert to an earlier update build. In that situation, Add/Remove Programs entries point to non-existing binaries, and therefore the uninstall process does not work. Therefore, Microsoft strongly encourages you to keep the folder and its contents intact.
Ok. I have no plans to ever downgrade or uninstall an SP or CU, so I should be ok, right? Well, there are other references, such as this one:
in which someone referenced the following KB article:
which states (emphasis added):
When you install SQL Server, the Windows Installer stores critical files in the Windows Installer Cache (default is C:\Windows\Installer). These files are required for uninstalling and updating applications.
Now, this particular article seems specific to the C:\Windows\Installer folder, and I am not talking about deleting from that folder. Still, due to the mention of the possibility of not being able to apply updates, I wanted more info first.
Has anyone removed these folders before, or at least just their contents? If so, were there any negative effects? These folders only ever increase. I just applied the "Spectre / Meltdown" patches for all four versions and the totals increased by 3.65 GB and 6,900 files (the end result being the figures shown in the chart above).
To be clear, I am not looking for should I or shouldn't I remove one or both of these folders; I am looking for can I or can't I remove one or both (without breaking anything more than the ability to uninstall / downgrade, which I already accept as a consequence).