branches/zip: Add statistics on page compression and decompression counts.

ha_innodb.cc: Add the columns COMPRESSED, COMPRESSED_OK, DECOMPRESSED
to INFORMATION_SCHEMA.INNODB_BUDDY.

page_zip_compress_count[], page_zip_compress_ok[]: New statistic counters,
incremented in page_zip_compress().

page_zip_decompress_count[]: New statistic counter,
incremented in page_zip_decompress().

handler/ha_innodb.cc

@@ -8775,14 +8775,29 @@ innobase_is_buddy_fill(
 {
 	TABLE*	table	= (TABLE *) tables->table;
 	int	status	= 0;
+	uint	y	= 0;
 
 	DBUG_ENTER("innobase_is_buddy_fill");
+
+	/* Determine log2(PAGE_ZIP_MIN_SIZE / 2 / BUF_BUDDY_LOW). */
+	for (uint r = PAGE_ZIP_MIN_SIZE / 2 / BUF_BUDDY_LOW; r >>= 1; y++);
+
 	mutex_enter_noninline(&buf_pool->mutex);
 
 	for (uint x = 0; x <= BUF_BUDDY_SIZES; x++) {
 		table->field[0]->store(BUF_BUDDY_LOW << x);
 		table->field[1]->store(buf_buddy_relocated[x]);
-		table->field[2]->store(buf_buddy_used[x]);
+		if (x > y) {
+			const uint i = x - y;
+			table->field[2]->store(page_zip_compress_count[i]);
+			table->field[3]->store(page_zip_compress_ok[i]);
+			table->field[4]->store(page_zip_decompress_count[i]);
+		} else {
+			table->field[2]->store(0);
+			table->field[3]->store(0);
+			table->field[4]->store(0);
+		}
+		table->field[5]->store(buf_buddy_used[x]);
 
 		if (schema_table_store_record(thd, table)) {
 			status = 1;
@@ -8799,6 +8814,12 @@ static ST_FIELD_INFO innobase_is_buddy_fields[] =
 {
   {"SIZE", 5, MYSQL_TYPE_LONG, 0, 0, "Block Size"},
   {"RELOCATED", 21, MYSQL_TYPE_LONG, 0, 0, "Total Number of Relocations"},
+  {"COMPRESSED", 21, MYSQL_TYPE_LONG, 0, 0,
+   "Total Number of Compressions"},
+  {"COMPRESSED_OK", 21, MYSQL_TYPE_LONG, 0, 0,
+   "Total Number of Successful Compressions"},
+  {"DECOMPRESSED", 21, MYSQL_TYPE_LONG, 0, 0,
+   "Total Number of Decompressions"},
   {"USED", 21, MYSQL_TYPE_LONG, 0, 0, "Currently in Use"},
   {0, 0, MYSQL_TYPE_STRING, 0, 0, 0}
 };

include/page0types.h

@@ -42,11 +42,19 @@ struct page_zip_des_struct
 					columns on the page; the maximum
 					is 744 on a 16 KiB page */
 	unsigned	ssize:3;	/* 0 or compressed page size;
-					the size in bytes is 512<<ssize. */
+					the size in bytes is
+					PAGE_ZIP_MIN_SIZE << (ssize - 1). */
 };
 
 #define PAGE_ZIP_MIN_SIZE	1024	/* smallest page_zip_des_struct.size */
 
+/** Number of page compressions, indexed by page_zip_des_t::ssize */
+extern ulint	page_zip_compress_count[8];
+/** Number of successful page compressions, indexed by page_zip_des_t::ssize */
+extern ulint	page_zip_compress_ok[8];
+/** Number of page decompressions, indexed by page_zip_des_t::ssize */
+extern ulint	page_zip_decompress_count[8];
+
 /**************************************************************************
 Write data to the compressed page.  The data must already be written to
 the uncompressed page. */

page/page0zip.c

@@ -25,6 +25,13 @@ Created June 2005 by Marko Makela
 #include "log0recv.h"
 #include "zlib.h"
 
+/** Number of page compressions, indexed by page_zip_des_t::ssize */
+ulint	page_zip_compress_count[8];
+/** Number of successful page compressions, indexed by page_zip_des_t::ssize */
+ulint	page_zip_compress_ok[8];
+/** Number of page decompressions, indexed by page_zip_des_t::ssize */
+ulint	page_zip_decompress_count[8];
+
 /* Please refer to ../include/page0zip.ic for a description of the
 compressed page format. */
 
@@ -1062,6 +1069,8 @@ page_zip_compress(
 			n_fields, n_dense);
 	}
 #endif /* UNIV_DEBUG || UNIV_ZIP_DEBUG */
+	page_zip_compress_count[page_zip->ssize]++;
+
 	if (UNIV_UNLIKELY(n_dense * PAGE_ZIP_DIR_SLOT_SIZE
 			  >= page_zip_get_size(page_zip))) {
 		return(FALSE);
@@ -1224,6 +1233,8 @@ page_zip_compress(
 		page_zip_compress_write_log(page_zip, page, index, mtr);
 	}
 
+	page_zip_compress_ok[page_zip->ssize]++;
+
 	return(TRUE);
 }
 
@@ -2588,6 +2599,7 @@ page_zip_decompress(
 
 	page_zip_fields_free(index);
 	mem_heap_free(heap);
+	page_zip_decompress_count[page_zip->ssize]++;
 
 	return(TRUE);
 }