diff --git a/netlib/src/main/java/smile/netlib/NLMatrix.java b/netlib/src/main/java/smile/netlib/NLMatrix.java
index d36aa6df8..0a60d8e94 100644
--- a/netlib/src/main/java/smile/netlib/NLMatrix.java
+++ b/netlib/src/main/java/smile/netlib/NLMatrix.java
@@ -258,9 +258,9 @@ public QR qr() {
         int lwork = n;
         if (info.val == 0) {
             lwork = (int) work[0];
-            logger.info("LAPACK DEGQRF returns work space size: {}", lwork);
+            logger.debug("LAPACK DEGQRF returns work space size: {}", lwork);
         } else {
-            logger.info("LAPACK DEGQRF error code: {}", info.val);
+            logger.warn("LAPACK DEGQRF error code: {}", info.val);
         }
 
         lwork = Math.max(1, lwork);
@@ -302,9 +302,9 @@ public SVD svd() {
         int lwork = 3 * mn + Math.max(mx, 5*mn*mn + 4 *mn);
         if (info.val == 0) {
             lwork = (int) work[0];
-            logger.info("LAPACK DGESDD returns work space size: {}", lwork);
+            logger.debug("LAPACK DGESDD returns work space size: {}", lwork);
         } else {
-            logger.info("LAPACK DGESDD error code: {}", info.val);
+            logger.warn("LAPACK DGESDD error code: {}", info.val);
         }
 
         lwork = Math.max(1, lwork);
@@ -350,9 +350,9 @@ NLMatrix.Lower, n, data(), ld(), 0, 0, 0, 0, abstol,
             if (info.val == 0) {
                 lwork = (int) work[0];
                 liwork = (int) iwork[0];
-                logger.info("LAPACK DSYEVR returns work space size: {}", lwork);
+                logger.debug("LAPACK DSYEVR returns work space size: {}", lwork);
             } else {
-                logger.info("LAPACK DSYEVR error code: {}", info.val);
+                logger.warn("LAPACK DSYEVR error code: {}", info.val);
             }
 
             lwork = Math.max(1, lwork);
@@ -393,9 +393,9 @@ NLMatrix.Lower, n, data(), ld(), 0, 0, 0, 0, abstol,
             int lwork = 4 * n;
             if (info.val == 0) {
                 lwork = (int) work[0];
-                logger.info("LAPACK DGEEV returns work space size: {}", lwork);
+                logger.debug("LAPACK DGEEV returns work space size: {}", lwork);
             } else {
-                logger.info("LAPACK DGEEV error code: {}", info.val);
+                logger.warn("LAPACK DGEEV error code: {}", info.val);
             }
 
             lwork = Math.max(1, lwork);
@@ -449,9 +449,9 @@ NLMatrix.Lower, n, data(), ld(), 0, 0, 0, 0, abstol,
             if (info.val == 0) {
                 lwork = (int) work[0];
                 liwork = (int) iwork[0];
-                logger.info("LAPACK DSYEVR returns work space size: {}", lwork);
+                logger.debug("LAPACK DSYEVR returns work space size: {}", lwork);
             } else {
-                logger.info("LAPACK DSYEVR error code: {}", info.val);
+                logger.warn("LAPACK DSYEVR error code: {}", info.val);
             }
 
             lwork = Math.max(1, lwork);
@@ -486,9 +486,9 @@ NLMatrix.Lower, n, data(), ld(), 0, 0, 0, 0, abstol,
             int lwork = 4 * n;
             if (info.val == 0) {
                 lwork = (int) work[0];
-                logger.info("LAPACK DGEEV returns work space size: {}", lwork);
+                logger.debug("LAPACK DGEEV returns work space size: {}", lwork);
             } else {
-                logger.info("LAPACK DGEEV error code: {}", info.val);
+                logger.warn("LAPACK DGEEV error code: {}", info.val);
             }
 
             lwork = Math.max(1, lwork);
diff --git a/netlib/src/main/java/smile/netlib/QR.java b/netlib/src/main/java/smile/netlib/QR.java
index c6c329d0f..423dde5ce 100644
--- a/netlib/src/main/java/smile/netlib/QR.java
+++ b/netlib/src/main/java/smile/netlib/QR.java
@@ -92,9 +92,9 @@ public DenseMatrix getQ() {
         int lwork = n;
         if (info.val == 0) {
             lwork = (int) work[0];
-            logger.info("LAPACK DORGQR returns work space size: {}", lwork);
+            logger.debug("LAPACK DORGQR returns work space size: {}", lwork);
         } else {
-            logger.info("LAPACK DORGQR error code: {}", info.val);
+            logger.warn("LAPACK DORGQR error code: {}", info.val);
         }
 
         lwork = Math.max(1, lwork);
@@ -151,9 +151,9 @@ public void solve(DenseMatrix B) {
         int lwork = n;
         if (info.val == 0) {
             lwork = (int) work[0];
-            logger.info("LAPACK DORMQR returns work space size: {}", lwork);
+            logger.debug("LAPACK DORMQR returns work space size: {}", lwork);
         } else {
-            logger.info("LAPACK DORMQR error code: {}", info.val);
+            logger.warn("LAPACK DORMQR error code: {}", info.val);
         }
 
         lwork = Math.max(1, lwork);