On my test site there is no problem at all rebuilding index with 2.2 but as soon as I install xf 2.3 / ES 2.3 and try to rebuild index I am getting the error there is not enough memory. Spoke to host (Mattw) who suggested this is a bug because he tells me what I'm trying to do with rebuilding index is asking for over 1GB of memory for php.
If i run it via admin cp I get a 503 service unavalible error.
I used cli and I thought it was successful but may be in was killed in the backround I'm not sure