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Commit 1ba7ae75 authored by Marko Mäkelä's avatar Marko Mäkelä
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Bug#12835650 VARCHAR maximum length performance impact 

row_sel_field_store_in_mysql_format(): Do not pad the unused part of
the buffer reserved for a True VARCHAR column (introduced in 5.0.3).
Add Valgrind instrumentation ensuring that the unused part will be
flagged uninitialized.

row_sel_copy_cached_field_for_mysql(): New function: Copy a field
that is in the MySQL row format, not copying the unused tail of
VARCHAR columns.

row_sel_pop_cached_row_for_mysql(): Invoke
row_sel_copy_cached_field_for_mysql() for copying fields.
When the row is long, copy it field-by-field.

rb:715 approved by Inaam Rana
parent 7e8d625b
Show whitespace changes
Inline Side-by-side
Showing with 132 additions and 47 deletions
storage/innobase/row/row0sel.c
View file @ 1ba7ae75
......@@ -2468,6 +2468,8 @@ row_sel_field_store_in_mysql_format(
ut_ad(len != UNIV_SQL_NULL);
UNIV_MEM_ASSERT_RW(data, len);
UNIV_MEM_ASSERT_W(dest, templ->mysql_col_len);
UNIV_MEM_INVALID(dest, templ->mysql_col_len);
if (templ->type == DATA_INT) {
/* Convert integer data from Innobase to a little-endian
......@@ -2502,14 +2504,16 @@ row_sel_field_store_in_mysql_format(
dest = row_mysql_store_true_var_len(
dest, len, templ->mysql_length_bytes);
/* Copy the actual data. Leave the rest of the
buffer uninitialized. */
ut_memcpy(dest, data, len);
return;
}
/* Copy the actual data */
ut_memcpy(dest, data, len);
/* Pad with trailing spaces. We pad with spaces also the
unused end of a >= 5.0.3 true VARCHAR column, just in case
MySQL expects its contents to be deterministic. */
/* Pad with trailing spaces. */
pad_ptr = dest + len;
......@@ -3012,6 +3016,39 @@ sel_restore_position_for_mysql(
return(TRUE);
}
/************************************************************************
Copies a cached field for MySQL from the fetch cache. */
static
void
row_sel_copy_cached_field_for_mysql(
/*================================*/
byte* buf, /* in/out: row buffer */
byte* cache, /* in: cached row */
const mysql_row_templ_t*templ) /* in: column template */
{
ulint len;
buf += templ->mysql_col_offset;
cache += templ->mysql_col_offset;
UNIV_MEM_ASSERT_W(buf, templ->mysql_col_len);
if (templ->mysql_type == DATA_MYSQL_TRUE_VARCHAR
&& templ->type != DATA_INT) {
/* Check for != DATA_INT to make sure we do
not treat MySQL ENUM or SET as a true VARCHAR!
Find the actual length of the true VARCHAR field. */
row_mysql_read_true_varchar(
&len, cache, templ->mysql_length_bytes);
len += templ->mysql_length_bytes;
UNIV_MEM_INVALID(buf, templ->mysql_col_len);
} else {
len = templ->mysql_col_len;
}
ut_memcpy(buf, cache, len);
}
/************************************************************************
Pops a cached row for MySQL from the fetch cache. */
UNIV_INLINE
......@@ -3028,22 +3065,18 @@ row_sel_pop_cached_row_for_mysql(
ut_ad(prebuilt->n_fetch_cached > 0);
ut_ad(prebuilt->mysql_prefix_len <= prebuilt->mysql_row_len);
UNIV_MEM_ASSERT_W(buf, prebuilt->mysql_row_len);
cached_rec = prebuilt->fetch_cache[prebuilt->fetch_cache_first];
if (UNIV_UNLIKELY(prebuilt->keep_other_fields_on_keyread)) {
/* Copy cache record field by field, don't touch fields that
are not covered by current key */
cached_rec = prebuilt->fetch_cache[
prebuilt->fetch_cache_first];
for (i = 0; i < prebuilt->n_template; i++) {
templ = prebuilt->mysql_template + i;
#if 0 /* Some of the cached_rec may legitimately be uninitialized. */
UNIV_MEM_ASSERT_RW(cached_rec
+ templ->mysql_col_offset,
templ->mysql_col_len);
#endif
ut_memcpy(buf + templ->mysql_col_offset,
cached_rec + templ->mysql_col_offset,
templ->mysql_col_len);
row_sel_copy_cached_field_for_mysql(
buf, cached_rec, templ);
/* Copy NULL bit of the current field from cached_rec
to buf */
if (templ->mysql_null_bit_mask) {
......@@ -3053,17 +3086,24 @@ row_sel_pop_cached_row_for_mysql(
& (byte)templ->mysql_null_bit_mask;
}
}
} else if (prebuilt->mysql_prefix_len > 63) {
/* The record is long. Copy it field by field, in case
there are some long VARCHAR column of which only a
small length is being used. */
UNIV_MEM_INVALID(buf, prebuilt->mysql_prefix_len);
/* First copy the NULL bits. */
ut_memcpy(buf, cached_rec, prebuilt->null_bitmap_len);
/* Then copy the requested fields. */
for (i = 0; i < prebuilt->n_template; i++) {
row_sel_copy_cached_field_for_mysql(
buf, cached_rec, prebuilt->mysql_template + i);
}
else {
#if 0 /* Some of the cached_rec may legitimately be uninitialized. */
UNIV_MEM_ASSERT_RW(prebuilt->fetch_cache
[prebuilt->fetch_cache_first],
prebuilt->mysql_prefix_len);
#endif
ut_memcpy(buf,
prebuilt->fetch_cache[prebuilt->fetch_cache_first],
prebuilt->mysql_prefix_len);
} else {
ut_memcpy(buf, cached_rec, prebuilt->mysql_prefix_len);
}
prebuilt->n_fetch_cached--;
prebuilt->fetch_cache_first++;
......
storage/innodb_plugin/ChangeLog
View file @ 1ba7ae75
2011-08-08 The InnoDB Team
* row/row0sel.c:
Fix Bug#12835650 VARCHAR maximum length performance impact
2011-08-08 The InnoDB Team
* handler/ha_innodb.cc:
......
storage/innodb_plugin/row/row0sel.c
View file @ 1ba7ae75
......@@ -2544,6 +2544,8 @@ row_sel_field_store_in_mysql_format(
ut_ad(len != UNIV_SQL_NULL);
UNIV_MEM_ASSERT_RW(data, len);
UNIV_MEM_ASSERT_W(dest, templ->mysql_col_len);
UNIV_MEM_INVALID(dest, templ->mysql_col_len);
switch (templ->type) {
case DATA_INT:
......@@ -2580,14 +2582,16 @@ row_sel_field_store_in_mysql_format(
dest = row_mysql_store_true_var_len(
dest, len, templ->mysql_length_bytes);
/* Copy the actual data. Leave the rest of the
buffer uninitialized. */
memcpy(dest, data, len);
break;
}
/* Copy the actual data */
ut_memcpy(dest, data, len);
/* Pad with trailing spaces. We pad with spaces also the
unused end of a >= 5.0.3 true VARCHAR column, just in case
MySQL expects its contents to be deterministic. */
/* Pad with trailing spaces. */
pad_ptr = dest + len;
......@@ -3119,6 +3123,39 @@ sel_restore_position_for_mysql(
return(TRUE);
}
/********************************************************************//**
Copies a cached field for MySQL from the fetch cache. */
static
void
row_sel_copy_cached_field_for_mysql(
/*================================*/
byte* buf, /*!< in/out: row buffer */
const byte* cache, /*!< in: cached row */
const mysql_row_templ_t*templ) /*!< in: column template */
{
ulint len;
buf += templ->mysql_col_offset;
cache += templ->mysql_col_offset;
UNIV_MEM_ASSERT_W(buf, templ->mysql_col_len);
if (templ->mysql_type == DATA_MYSQL_TRUE_VARCHAR
&& templ->type != DATA_INT) {
/* Check for != DATA_INT to make sure we do
not treat MySQL ENUM or SET as a true VARCHAR!
Find the actual length of the true VARCHAR field. */
row_mysql_read_true_varchar(
&len, cache, templ->mysql_length_bytes);
len += templ->mysql_length_bytes;
UNIV_MEM_INVALID(buf, templ->mysql_col_len);
} else {
len = templ->mysql_col_len;
}
ut_memcpy(buf, cache, len);
}
/********************************************************************//**
Pops a cached row for MySQL from the fetch cache. */
UNIV_INLINE
......@@ -3131,26 +3168,22 @@ row_sel_pop_cached_row_for_mysql(
{
ulint i;
const mysql_row_templ_t*templ;
byte* cached_rec;
const byte* cached_rec;
ut_ad(prebuilt->n_fetch_cached > 0);
ut_ad(prebuilt->mysql_prefix_len <= prebuilt->mysql_row_len);
UNIV_MEM_ASSERT_W(buf, prebuilt->mysql_row_len);
cached_rec = prebuilt->fetch_cache[prebuilt->fetch_cache_first];
if (UNIV_UNLIKELY(prebuilt->keep_other_fields_on_keyread)) {
/* Copy cache record field by field, don't touch fields that
are not covered by current key */
cached_rec = prebuilt->fetch_cache[
prebuilt->fetch_cache_first];
for (i = 0; i < prebuilt->n_template; i++) {
templ = prebuilt->mysql_template + i;
#if 0 /* Some of the cached_rec may legitimately be uninitialized. */
UNIV_MEM_ASSERT_RW(cached_rec
+ templ->mysql_col_offset,
templ->mysql_col_len);
#endif
ut_memcpy(buf + templ->mysql_col_offset,
cached_rec + templ->mysql_col_offset,
templ->mysql_col_len);
row_sel_copy_cached_field_for_mysql(
buf, cached_rec, templ);
/* Copy NULL bit of the current field from cached_rec
to buf */
if (templ->mysql_null_bit_mask) {
......@@ -3160,17 +3193,24 @@ row_sel_pop_cached_row_for_mysql(
& (byte)templ->mysql_null_bit_mask;
}
}
} else if (prebuilt->mysql_prefix_len > 63) {
/* The record is long. Copy it field by field, in case
there are some long VARCHAR column of which only a
small length is being used. */
UNIV_MEM_INVALID(buf, prebuilt->mysql_prefix_len);
/* First copy the NULL bits. */
ut_memcpy(buf, cached_rec, prebuilt->null_bitmap_len);
/* Then copy the requested fields. */
for (i = 0; i < prebuilt->n_template; i++) {
row_sel_copy_cached_field_for_mysql(
buf, cached_rec, prebuilt->mysql_template + i);
}
else {
#if 0 /* Some of the cached_rec may legitimately be uninitialized. */
UNIV_MEM_ASSERT_RW(prebuilt->fetch_cache
[prebuilt->fetch_cache_first],
prebuilt->mysql_prefix_len);
#endif
ut_memcpy(buf,
prebuilt->fetch_cache[prebuilt->fetch_cache_first],
prebuilt->mysql_prefix_len);
} else {
ut_memcpy(buf, cached_rec, prebuilt->mysql_prefix_len);
}
prebuilt->n_fetch_cached--;
prebuilt->fetch_cache_first++;
......
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