+my $bs = $opt->{batchsize} // $cfg->{lc('publicInbox.indexBatchSize')};
+if (defined $bs) {
+ PublicInbox::Admin::parse_unsigned(\$bs) or
+ die "`publicInbox.indexBatchSize=$bs' not parsed\n";
+}
+local $PublicInbox::SearchIdx::BATCH_BYTES = $bs if defined($bs);
+
+# out-of-the-box builds of Xapian 1.4.x are still limited to 32-bit
+# https://getting-started-with-xapian.readthedocs.io/en/latest/concepts/indexing/limitations.html
+local $ENV{XAPIAN_FLUSH_THRESHOLD} ||= '4294967295' if defined($bs);
+
+my $s = $opt->{sequentialshard} //
+ $cfg->{lc('publicInbox.indexSequentialShard')};
+if (defined $s) {
+ my $v = $cfg->git_bool($s);
+ defined($v) or
+ die "`publicInbox.indexSequentialShard=$s' not boolean\n";
+ $opt->{sequentialshard} = $v;
+}
+
+my $mods = {};