diff --git a/R/data.table.R b/R/data.table.R
index c64c391b3..f89f6c33e 100644
--- a/R/data.table.R
+++ b/R/data.table.R
@@ -147,7 +147,7 @@ replace_dot_alias = function(e) {
   }
 }
 
-"[.data.table" = function(x, i, j, by, keyby, with=TRUE, nomatch=NA, mult="all", roll=FALSE, rollends=if (roll=="nearest") c(TRUE,TRUE) else if (roll>=0.0) c(FALSE,TRUE) else c(TRUE,FALSE), which=FALSE, .SDcols, verbose=getOption("datatable.verbose"), allow.cartesian=getOption("datatable.allow.cartesian"), drop=NULL, on=NULL, env=NULL, showProgress=getOption("datatable.showProgress", interactive()))
+"[.data.table" = function(x, i, j, by, keyby, with=TRUE, nomatch=NA, mult="all", roll=FALSE, rollends=if (roll=="nearest") c(TRUE,TRUE) else if (roll>=0.0) c(FALSE,TRUE) else c(TRUE,FALSE), which=FALSE, .SDcols, verbose=getOption("datatable.verbose"), allow.cartesian=getOption("datatable.allow.cartesian"), drop=NULL, on=NULL, env=NULL, showProgress=as.integer(getOption("datatable.showProgress", interactive())))
 {
   # ..selfcount <<- ..selfcount+1  # in dev, we check no self calls, each of which doubles overhead, or could
   # test explicitly if the caller is [.data.table (even stronger test. TO DO.)
@@ -244,7 +244,7 @@ replace_dot_alias = function(e) {
   if ((isTRUE(which)||is.na(which)) && !missing(j)) stopf("which==%s (meaning return row numbers) but j is also supplied. Either you need row numbers or the result of j, but only one type of result can be returned.", which)
   if (is.null(nomatch) && is.na(which)) stopf("which=NA with nomatch=0|NULL would always return an empty vector. Please change or remove either which or nomatch.")
   if (!with && missing(j)) stopf("j must be provided when with=FALSE")
-  if (!missing(by) && !isTRUEorFALSE(showProgress)) stopf("%s must be TRUE or FALSE", "showProgress")
+  if (!missing(by) && !is.numeric(showProgress)) stopf("%s must be numeric.", "showProgress")
   irows = NULL  # Meaning all rows. We avoid creating 1:nrow(x) for efficiency.
   notjoin = FALSE
   rightcols = leftcols = integer()
@@ -1934,7 +1934,7 @@ replace_dot_alias = function(e) {
     }
     ans = c(g, ans)
   } else {
-    ans = .Call(Cdogroups, x, xcols, groups, grpcols, jiscols, xjiscols, grporder, o__, f__, len__, jsub, SDenv, cols, newnames, !missing(on), verbose, showProgress)
+    ans = .Call(Cdogroups, x, xcols, groups, grpcols, jiscols, xjiscols, grporder, o__, f__, len__, jsub, SDenv, cols, newnames, !missing(on), verbose, as.integer(showProgress))
   }
   # unlock any locked data.table components of the answer, #4159
   # MAX_DEPTH prevents possible infinite recursion from truly recursive object, #4173
diff --git a/src/dogroups.c b/src/dogroups.c
index d4f774568..43d1e97fa 100644
--- a/src/dogroups.c
+++ b/src/dogroups.c
@@ -87,9 +87,10 @@ SEXP dogroups(SEXP dt, SEXP dtcols, SEXP groups, SEXP grpcols, SEXP jiscols, SEX
   SEXP SDall = PROTECT(findVar(install(".SDall"), env)); nprotect++;  // PROTECT for rchk
   SEXP SD = PROTECT(findVar(install(".SD"), env)); nprotect++;
   
-  const bool showProgress = LOGICAL(showProgressArg)[0]==1 && ngrp > 1; // showProgress only if more than 1 group
+  int updateTime = INTEGER(showProgressArg)[0];
+  const bool showProgress = updateTime > 0 && ngrp > 1; // showProgress only if more than 1 group
   double startTime = (showProgress) ? wallclock() : 0; // For progress printing, startTime is set at the beginning
-  double nextTime = (showProgress) ? startTime+3 : 0; // wait 3 seconds before printing progress
+  double nextTime = (showProgress) ? startTime + MAX(updateTime, 3) : 0; // wait at least 3 seconds before printing progress
 
   defineVar(sym_BY, BY = PROTECT(allocVector(VECSXP, ngrpcols)), env); nprotect++;  // PROTECT for rchk
   SEXP bynames = PROTECT(allocVector(STRSXP, ngrpcols));  nprotect++;   // TO DO: do we really need bynames, can we assign names afterwards in one step?
@@ -456,7 +457,7 @@ SEXP dogroups(SEXP dt, SEXP dtcols, SEXP groups, SEXP grpcols, SEXP jiscols, SEX
         Rprintf(_("Processed %d groups out of %d. %.0f%% done. Time elapsed: %ds. ETA: %ds."), i+1, ngrp, 100.0*(i+1)/ngrp, (int)(now-startTime), ETA);
         // # nocov end
       }
-      nextTime = now+1;
+      nextTime = now+updateTime;
       hasPrinted = true;
     }
     ansloc += maxn;