@richard ,
There can be multiple reasons for seeing large number of mutations remaining on the indexes page. One could be a rollback on indexer side. I do not see any rollback related messages in the logs you shared. Other could be due to documents being pumped/updated into the bucket. When you see the increase in “mutations remaining”, are there any documents being written into the “main” bucket?
Also, 1,426,675 mutations remaining does not necessarily mean 1,426,675 documents are to be processed as multiple document updates will be de-duplicated and sent to clients. This number is just an upper limit on how many mutations may have to be processed. In practise, the actual number of documents being processed could be lot less than this.
Also, the resident percent of all the indexes seem “0”. This means that majority of the index data is on disk. Any update, read or write of index data will requires a disk access and this can slow down the system. I see that you have reduced the memory quota for indexes - This does not help at all. I think you should consider increasing the memory quota for the indexes.
Thanks,
Varun