Schema Compare slow and then fails

[Whalee110]

Type: Bug

Using Schema compare on an object is quite slow compared to ADS version 1.44 (Which the extension no longer works for)

Previously clicking the "compare" button would show results within a few minutes, now it can take over 30 minutes. Once compare is complete and changes are selected choosing the "apply" option has no effect or output with the button becoming possible to press after a few minutes.

Expectation is, compare loads and then apply will update the project with the changes.

The --trustserver flag was testing to see if helped it at all but it did not. Same outcome without it.

Extension version: 1.21.0
Azure Data Studio version: azuredatastudio 1.46.1 (ba29842, 2023-10-02T18:14:22.887Z)
OS version: Windows_NT x64 10.0.22621
Restricted Mode: No
Preview Features: Enabled
Modes:

System Info

Item	Value
CPUs	12th Gen Intel(R) Core(TM) i7-1255U (12 x 2611)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: disabled_off direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok video_decode: enabled video_encode: enabled vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: enabled
Load (avg)	undefined
Memory (System)	31.64GB (18.50GB free)
Process Argv	--trust-server-certificate
Screen Reader	yes
VM	0%

[kisantia]

Whalee110 was schema compare also slow in ADS 1.45.1?

If needed, you can download older versions of the schema compare extension and manually install it, which will work with ADS 1.44 ex: https://sqlopsextensions.blob.core.windows.net/extensions/schema-compare/schema-compare-1.19.0.vsix

[Whalee110]

Thank you for that, that will help alot - The extension that upgraded though was SQL Projects - Do you have a link for that one too?

The Schema Compare extension did seem to break where it cut off most of the output window so I could only "see" 1 row at a time, but I believe that is more likely from extensions updates so I will give that a try.

If there are any logs I can provide for info on the above let me know! I couldn't find any info except the internal logs saying "check logs"

[SakshiS-harma]

Whalee110 If you are on 1.3.1 of SQL Projects and want to test with the older version, you can try: https://sqlopsextensions.blob.core.windows.net/extensions/sql-database-projects/sql-database-projects-1.2.0.vsix to access it. It is compatible with ADS 1.44

[Whalee110]

An update that may help.

I downgraded ADS to 1.45.1 and downgraded all extensions to work, Schema Compare 1.19.0 and Database Projects 1.1.1 - This has no change in the performance in running Schema Compare within database projects still took well over 30 minutes and then would not function when attempting to "apply"

Downgrading ADS to 1.44.1 and Schema Compare 1.19.0 with Database Projects 1.2.0 completes the compare within a few minutes as expected but the "apply" is still not functioning in updating the project. I am going to attempt another clean install then try again.

[Whalee110]

So Schema Compare taking excessive time seems to be tied to ADS 1.45.1 +

Apply not working based on developer tool console seems to occur when there is an error during the compare selecting what to include etc. It then gives this output when you attempt to hit apply. (This is when I have loaded a .scmp files or started from scratch but have selected and deselected what you want to update)

[[object Object]]Cannot read properties of undefined (reading 'sourceValue')

If I don't deselect any items the apply works as intended.

[SakshiS-harma]

Whalee110 as for the apply not working- this is currently a known issue where include/excluding changes takes some time in the background (there is no visual notification of if the include/exclude calculation has finalized). So, waiting out a little bit (a couple of mins may be depending on how big the schema is) and then trying Apply should ideally work.
Do let us know if that doesn't work. Thanks!

[Whalee110]

I am currently using 1.44, Database projects 1.1.1 and Schema compare 1.19.0. This combination functions as intended.

Database projects 1.3.1 / Schema compare 1.21.0 breaks the compare, within ADS 1.44 the compare window becomes incredibly small only showing at most 1 row at a time in the "Selection" and you cannot adjust it's size. (This may be due to the change in Schema compare that made the window resizable? - that was only other issue I saw similar to it)

Updating to 1.45 or 1.46 fixes that but then the compare only portion goes from a minute or so to take 30 minutes.

The apply does take a big chunk of time with no visual in both, so that itself isn't too bad but the 30 minute wait just for the compare is a huge impact.

[kisantia]

The DacFx version used by schema compare was updated in insiders and some performance slowdowns were fixed - Whalee110 can you try using the latest insiders release and see if it's any better?

If not, then there a couple other things we'll ask you to try to help pinpoint where this slowdown was introduced in the DacFx codebase.