diff --git a/sys/geom/mirror/g_mirror.c b/sys/geom/mirror/g_mirror.c
index 61cec14ac689..dd8c58419b0c 100644
--- a/sys/geom/mirror/g_mirror.c
+++ b/sys/geom/mirror/g_mirror.c
@@ -896,8 +896,7 @@ g_mirror_sync_one(struct g_mirror_disk *disk)
 	bp->bio_parent = NULL;
 	bp->bio_cmd = BIO_READ;
 	bp->bio_offset = disk->d_sync.ds_offset;
-	bp->bio_length = MIN(G_MIRROR_SYNC_BLOCK_SIZE,
-	    sc->sc_mediasize - bp->bio_offset);
+	bp->bio_length = MIN(MAXPHYS, sc->sc_mediasize - bp->bio_offset);
 	bp->bio_cflags = 0;
 	bp->bio_done = g_mirror_sync_done;
 	bp->bio_data = disk->d_sync.ds_data;
@@ -980,8 +979,7 @@ g_mirror_sync_request(struct bio *bp)
 			g_mirror_event_send(disk, G_MIRROR_DISK_STATE_ACTIVE,
 			    G_MIRROR_EVENT_DONTWAIT);
 			return;
-		} else if (sync->ds_offset_done %
-		    (G_MIRROR_SYNC_BLOCK_SIZE * 100) == 0) {
+		} else if (sync->ds_offset_done % (MAXPHYS * 100) == 0) {
 			/*
 			 * Update offset_done on every 100 blocks.
 			 * XXX: This should be configurable.
@@ -1236,8 +1234,7 @@ g_mirror_register_request(struct bio *bp)
 				    (bp->bio_offset < sync->ds_resync ||
 				     sync->ds_resync == -1)) {
 					sync->ds_resync = bp->bio_offset -
-					    (bp->bio_offset %
-					    G_MIRROR_SYNC_BLOCK_SIZE);
+					    (bp->bio_offset % MAXPHYS);
 				}
 				break;
 			default:
@@ -1574,8 +1571,7 @@ g_mirror_sync_start(struct g_mirror_disk *disk)
 	error = g_access(disk->d_sync.ds_consumer, 1, 0, 0);
 	KASSERT(error == 0, ("Cannot open %s (error=%d).",
 	    disk->d_softc->sc_name, error));
-	disk->d_sync.ds_data = malloc(G_MIRROR_SYNC_BLOCK_SIZE, M_MIRROR,
-	    M_WAITOK);
+	disk->d_sync.ds_data = malloc(MAXPHYS, M_MIRROR, M_WAITOK);
 	sc->sc_sync.ds_ndisks++;
 }
 
diff --git a/sys/geom/mirror/g_mirror.h b/sys/geom/mirror/g_mirror.h
index 060de9136af9..59490054a80f 100644
--- a/sys/geom/mirror/g_mirror.h
+++ b/sys/geom/mirror/g_mirror.h
@@ -84,8 +84,6 @@ extern u_int g_mirror_debug;
 	}								\
 } while (0)
 
-#define	G_MIRROR_SYNC_BLOCK_SIZE	131072
-
 #define	G_MIRROR_BIO_FLAG_REGULAR	0x01
 #define	G_MIRROR_BIO_FLAG_SYNC		0x02
 
diff --git a/sys/geom/raid3/g_raid3.c b/sys/geom/raid3/g_raid3.c
index 53f98582116e..36c0dd5533de 100644
--- a/sys/geom/raid3/g_raid3.c
+++ b/sys/geom/raid3/g_raid3.c
@@ -1229,8 +1229,7 @@ g_raid3_sync_one(struct g_raid3_softc *sc)
 	bp->bio_parent = NULL;
 	bp->bio_cmd = BIO_READ;
 	bp->bio_offset = disk->d_sync.ds_offset * (sc->sc_ndisks - 1);
-	bp->bio_length = MIN(G_RAID3_MAX_IO_SIZE,
-	    sc->sc_mediasize - bp->bio_offset);
+	bp->bio_length = MIN(MAXPHYS, sc->sc_mediasize - bp->bio_offset);
 	bp->bio_cflags = 0;
 	bp->bio_done = g_raid3_sync_done;
 	bp->bio_data = disk->d_sync.ds_data;
@@ -1347,8 +1346,7 @@ g_raid3_sync_request(struct bio *bp)
 			g_raid3_event_send(disk, G_RAID3_DISK_STATE_ACTIVE,
 			    G_RAID3_EVENT_DONTWAIT);
 			return;
-		} else if (sync->ds_offset_done %
-		    (G_RAID3_MAX_IO_SIZE * 100) == 0) {
+		} else if (sync->ds_offset_done % (MAXPHYS * 100) == 0) {
 			/*
 			 * Update offset_done on every 100 blocks.
 			 * XXX: This should be configurable.
@@ -1425,7 +1423,7 @@ g_raid3_register_request(struct bio *pbp)
 			break;
 		if (offset >= sync->ds_resync && sync->ds_resync != -1)
 			break;
-		sync->ds_resync = offset - (offset % G_RAID3_MAX_IO_SIZE);
+		sync->ds_resync = offset - (offset % MAXPHYS);
 		break;
 	    }
 	}
@@ -1830,7 +1828,7 @@ g_raid3_sync_start(struct g_raid3_softc *sc)
 	error = g_access(disk->d_sync.ds_consumer, 1, 0, 0);
 	KASSERT(error == 0, ("Cannot open %s (error=%d).",
 	    disk->d_softc->sc_name, error));
-	disk->d_sync.ds_data = malloc(G_RAID3_MAX_IO_SIZE, M_RAID3, M_WAITOK);
+	disk->d_sync.ds_data = malloc(MAXPHYS, M_RAID3, M_WAITOK);
 	sc->sc_syncdisk = disk;
 }
 
diff --git a/sys/geom/raid3/g_raid3.h b/sys/geom/raid3/g_raid3.h
index f28acb882d52..948d599930a1 100644
--- a/sys/geom/raid3/g_raid3.h
+++ b/sys/geom/raid3/g_raid3.h
@@ -84,8 +84,6 @@ extern u_int g_raid3_debug;
 	}								\
 } while (0)
 
-#define	G_RAID3_MAX_IO_SIZE	(DFLTPHYS * 2)
-
 #define	G_RAID3_BIO_CFLAG_REGULAR	0x01
 #define	G_RAID3_BIO_CFLAG_SYNC		0x02
 #define	G_RAID3_BIO_CFLAG_PARITY	0x04