The function SqlBlobStore::getBlobBatch has a fixme:
public function getBlobBatch( $blobAddresses, $queryFlags = 0 ) { // FIXME: All caching has temporarily been removed in I94c6f9ba7b9caeeb due to T235188. // Caching behavior should be restored by reverting I94c6f9ba7b9caeeb as soon as // the root cause of T235188 has been resolved.
Linking: T235188 / e1f8a8148d7329e01116ccf9133e58c6c0377f6b
The same comment was removed from WANObjectCache in 527fd0109fd62725aaaa80d9979b5f2f1348bf09
Please verify if it would be safe now to add caching back to that function (by reverting the hot fix)
The function is used by RevisionStore for batch requests of revisions records with the 'content' option and used to fetch big file metadata stored in the text blobs