lei: clamp internal worker processes to 4

"All" my CPUs is only 4, but it's probably ridiculous for
somebody with a 16-core system to have 16 processes for
accessing SQLite DBs.

We do the same thing in Pmdir for parallel Maildir access
(and V2Writable).

1 files changed, 3 insertions, 1 deletions

diff --git a/lib/PublicInbox/LeiImportKw.pm b/lib/PublicInbox/LeiImportKw.pm
index 2863d17f..379101c2 100644
--- a/lib/PublicInbox/LeiImportKw.pm
+++ b/lib/PublicInbox/LeiImportKw.pm
@@ -11,7 +11,9 @@ use parent qw(PublicInbox::IPC);
 sub new {
         my ($cls, $lei) = @_;
         my $self = bless { -wq_ident => 'lei import_kw worker' }, $cls;
-        my ($op_c, $ops) = $lei->workers_start($self, $self->detect_nproc);
+        my $j = $self->detect_nproc // 4;
+        $j = 4 if $j > 4;
+        my ($op_c, $ops) = $lei->workers_start($self, $j);
         $op_c->{ops} = $ops; # for PktOp->event_step
         $self->{lei_sock} = $lei->{sock};
         $lei->{ikw} = $self;