diff --git a/plugins/Full_CI_ZMQ/fci_zmq.irp.f b/plugins/Full_CI_ZMQ/fci_zmq.irp.f
index c80b7410..b3ffbe03 100644
--- a/plugins/Full_CI_ZMQ/fci_zmq.irp.f
+++ b/plugins/Full_CI_ZMQ/fci_zmq.irp.f
@@ -5,6 +5,7 @@ program fci_zmq
   
   double precision, allocatable  :: pt2(:)
   integer                        :: degree
+  integer                        :: n_det_before, to_select
   
   allocate (pt2(N_states))
   
@@ -33,13 +34,15 @@ program fci_zmq
   double precision               :: E_CI_before(N_states)
   
   
-  integer                        :: n_det_before
   print*,'Beginning the selection ...'
   E_CI_before(1:N_states) = CI_energy(1:N_states)
+  n_det_before = 0
   
   do while ( (N_det < N_det_max) .and. (maxval(abs(pt2(1:N_states))) > pt2_max) )
     n_det_before = N_det
-    call ZMQ_selection(max(1024-N_det, N_det), pt2)
+    to_select = max(1024-N_det, N_det)
+    to_select = min(to_select, N_det_max-n_det_before)
+    call ZMQ_selection(to_select, pt2)
     
     PROVIDE  psi_coef
     PROVIDE  psi_det
diff --git a/src/Utils/map_module.f90 b/src/Utils/map_module.f90
index 4a83582f..80260233 100644
--- a/src/Utils/map_module.f90
+++ b/src/Utils/map_module.f90
@@ -622,7 +622,7 @@ subroutine search_key_big_interval(key,X,sze,idx,ibegin_in,iend_in)
     
     istep = ishft(iend-ibegin,-1)
     idx = ibegin + istep
-    do while (istep > 16)
+    do while (istep > 64)
       idx = ibegin + istep
       ! TODO : Cache misses 
       if (cache_key < X(idx)) then
@@ -660,8 +660,8 @@ subroutine search_key_big_interval(key,X,sze,idx,ibegin_in,iend_in)
       endif
     enddo
     idx = ibegin
-    if (min(iend_in,sze) > ibegin+16) then
-      iend = ibegin+16
+    if (min(iend_in,sze) > ibegin+64) then
+      iend = ibegin+64
       do while (cache_key > X(idx))
         idx = idx+1
       end do
@@ -730,7 +730,7 @@ subroutine search_key_value_big_interval(key,value,X,Y,sze,idx,ibegin_in,iend_in
     
     istep = ishft(iend-ibegin,-1)
     idx = ibegin + istep
-    do while (istep > 16)
+    do while (istep > 64)
       idx = ibegin + istep
       if (cache_key < X(idx)) then
         iend = idx
@@ -771,8 +771,8 @@ subroutine search_key_value_big_interval(key,value,X,Y,sze,idx,ibegin_in,iend_in
     enddo
     idx = ibegin
     value = Y(idx)
-    if (min(iend_in,sze) > ibegin+16) then
-      iend = ibegin+16
+    if (min(iend_in,sze) > ibegin+64) then
+      iend = ibegin+64
       do while (cache_key > X(idx))
         idx = idx+1
         value = Y(idx)