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diff --git a/sys/geom/geom_io.c b/sys/geom/geom_io.c
--- a/sys/geom/geom_io.c
+++ b/sys/geom/geom_io.c
@@ -809,20 +809,17 @@
biotrack(bp, __func__);
if (pace != 0) {
/*
- * There has been at least one memory allocation
- * failure since the last I/O completed. Pause 1ms to
- * give the system a chance to free up memory. We only
- * do this once because a large number of allocations
- * can fail in the direct dispatch case and there's no
- * relationship between the number of these failures and
- * the length of the outage. If there's still an outage,
- * we'll pause again and again until it's
- * resolved. Older versions paused longer and once per
- * allocation failure. This was OK for a single threaded
- * g_down, but with direct dispatch would lead to max of
- * 10 IOPs for minutes at a time when transient memory
- * issues prevented allocation for a batch of requests
- * from the upper layers.
+ * There has been at least one memory allocation failure
+ * since the last I/O completed. Pause 1ms to give the
+ * system a chance to free up memory. Pause time is not
+ * scaled to the number of I/O failures since they tend
+ * to cluster and the number is not predictive of how
+ * long a pause is needed.
+ *
+ * Older versions had a longer pause, which limited the
+ * IOPS to 10, which prolonged memory shortages that could
+ * be alleviated by I/O completing since it eliminated
+ * direct dispatch as well.
*
* XXX This pacing is really lame. It needs to be solved
* by other methods. This is OK only because the worst
@@ -833,7 +830,7 @@
*/
CTR0(KTR_GEOM, "g_down pacing self");
pause_count++; /* g_down has only one thread */
- pause("g_down", min(hz/1000, 1));
+ pause_sbt("g_down", SBT_1MS, 0, 0);
pace = 0;
}
CTR2(KTR_GEOM, "g_down processing bp %p provider %s", bp,

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