os/bluestore: add a counter to trace rejected compress ops

This is useful for choosing a more proper bluestore_compression_required_ratio.

Signed-off-by: xie xingguo <xie.xingguo@zte.com.cn>

diff --git a/src/os/bluestore/BlueStore.cc b/src/os/bluestore/BlueStore.cc
index cd73bef1eedc477de7674e789516032ea73c9389..4b211e14306d0fe4e4a88b9e1c3d88aac6bcf477 100644 (file)
--- a/src/os/bluestore/BlueStore.cc
+++ b/src/os/bluestore/BlueStore.cc
@@ -2346,7 +2346,8 @@ void BlueStore::_init_logger()
     "Average checksum latency");
   b.add_u64(l_bluestore_compress_success_count, "compress_success_count",
     "Sum for beneficial compress ops");
-
+  b.add_u64(l_bluestore_compress_rejected_count, "compress_rejected_count",
+    "Sum for compress ops rejected due to low net gain of space");
   b.add_u64(l_bluestore_write_pad_bytes, "write_pad_bytes",
     "Sum for write-op padded bytes");
   b.add_u64(l_bluestore_wal_write_ops, "wal_write_ops",
@@ -7295,6 +7296,7 @@ int BlueStore::_do_alloc_write(
                  << ", which is more than required 0x" << dstlen
                  << ", leaving uncompressed"
                  << std::dec << dendl;
+        logger->inc(l_bluestore_compress_rejected_count);
       }
       logger->tinc(l_bluestore_compress_lat, ceph_clock_now(g_ceph_context) - start);
     }

diff --git a/src/os/bluestore/BlueStore.h b/src/os/bluestore/BlueStore.h
index 00818a3b522ce8cc345938419e38e83378104d48..0d996c3bf095f352b9b8063f477b59cb682dedce 100644 (file)
--- a/src/os/bluestore/BlueStore.h
+++ b/src/os/bluestore/BlueStore.h
@@ -62,6 +62,7 @@ enum {
   l_bluestore_decompress_lat,
   l_bluestore_csum_lat,
   l_bluestore_compress_success_count,
+  l_bluestore_compress_rejected_count,
   l_bluestore_write_pad_bytes,
   l_bluestore_wal_write_ops,
   l_bluestore_wal_write_bytes,