iPad stuck at 43% during optimization after iOS 27 download

You'll see a notification appear in the settings sidebar after updating to iOS/iPadOS 27 that your iPad is Optimising Search and Siri. This is entirely normal and as expected - and can take several days to complete the process.

While this notification remains visible, this indicates that (a) the expected reindexing process is running, and (b) you should anticipate impacted system performance while this background process continues to run.

Speaking of personal experience with both iPhone and iPad with iOS/iPadOS 27, the reindexing process continued for 36-48hrs - after which the settings sidebar notification disappeared and system performance dramatically improved.

As recommended by Apple, the indexing process can be hastened by leaving the device locked and connected to its Power Adapter while this process is running. Should you need to use the device, you can do so at the expense of indexing taking longer.

Thebestplacehere wrote:

Notification disappeared this morning after fully charged and connected Wi-Fi all night Took like a whole week Monday evening update to Sunday morning to finish indexing

Patience is key I guess

Indeed, you need to be patient while the reindexing process runs its course. The time required is heavily influenced by how much data needs to be processed, whether or not the iPad remains connected to an external power source, and how much you are using the iPad.

As recommended by Apple, the indexing process can be hastened by leaving the device locked and connected to its Power Adapter while this process is running. Should you need to use the device, you can do so at the expense of indexing taking longer. Anecdotal evidence suggests that two to three days (or longer) is needed.

Notification disappeared this morning after fully charged and connected Wi-Fi all night Took like a whole week Monday evening update to Sunday morning to finish indexing

Patience is key I guess

Same here stuck at 49% for few days now