but in buf_page_get_gen(). Adjust comments. This prevents
unnecessary decompression in read-ahead when the compressed block
exists in the buffer pool.
If the block does not exist in the buffer pool, read-ahead will still
allocate an uncompressed page and decompress the block.
Move buf_block_init_low() and buf_zip_decompress() earlier in the file,
because some compilers are unable to inline functions that are defined
after the invocation.
buf_page_get_gen(): Decompress the block if needed.
buf_page_init_for_read(): Do not decompress.
record does not contain externally stored columns.
page_zip_decompress_clust_ext(): New function for decompressing records
containing externally stored columns.
before testing create_info->avg_row_length, because otherwise the table
would be converted to uncompressed format by CREATE INDEX and possibly
other statements.
externally stored columns.
page_zip_compress_clust_ext(), page_zip_apply_log_ext():
New functions.
page_zip_compress_clust(), page_zip_apply_log(): Check rec_offs_any_extern()
and avoid invoking the costly loop in most cases.
Similar optimizations can be made in page_zip_decompress_clust() and
page_zip_write_rec().
by adding the REC_OFFS_EXTERNAL flag to rec_offs_base(offsets)[0].
This reduces the processor usage of page_zip_write_rec() by about 40%
in one test case. The code could be sped up further by testing
rec_offs_any_extern() outside of loops that check rec_offs_nth_extern().
The vast majority of records does not contain any externally stored columns.
page_cur_insert_rec_zip_reorg(): New function: Recompress or
reorganize a compressed page.
page_cur_insert_rec_zip(): New function: insert a record to
a compressed page.
page_cur_insert_rec_low(): Only handle inserts to uncompressed pages.
trx_undo_page_report_modify(), trx_undo_report_row_operation():
Add const qualifier to the parameter rec. Remove some local variables.
trx_undo_report_row_operation(): Invoke rec_get_offsets() only once.
to tables.
dict_mem_table_add_col(): Add the parameter "heap" for temporary memory
allocation. Allow it and "name" to be NULL. These parameters are NULL
when creating dummy indexes.
dict_add_col_name(): Remove calls to ut_malloc() and ut_free().
dict_table_get_col_name(): Allow table->col_names to be NULL.
dict_table_add_system_columns(), dict_table_add_to_cache():
Add the parameter "heap".
page_zip_set_alloc(): New function, to configure zlib to use a memory heap.
btr_store_big_rec_extern_fields(): Reduce memLevel, so that a heap of
256 kilobytes will suffice. Use page_zip_set_alloc().
btr_copy_externally_stored_field_prefix_low(): Use page_zip_set_alloc().
page_zip_compress(), page_zip_decompress(): Use page_zip_set_alloc().
of HASH_DELETE().
HASH_ASSERT_VALID(), HASH_INVALIDATE(): New macros, used in HASH_DELETE()
and HASH_SEARCH().
buf_page_init_low(): Add HASH_INVALIDATE(bpage, hash);
buf_page_init(): Call buf_page_init_low() before HASH_INSERT(), so that
bpage->hash will not be invalidated.
block->page.buf_fix_count. This mistake was made in r1255.
When access to the block is requested by some other thread,
buf_fix_count can be incremented during the execution of
buf_zip_decompress().
initialize all the fields of the control block.
buf_block_init_low(), buf_page_init_low(): New functions, used in
buf_page_init_for_backup_restore(), buf_page_init(), and
buf_page_init_for_read().
buf_buddy_relocate_block(): New function, split from buf_buddy_relocate().
Return FALSE when buf_page_can_relocate() returns FALSE.
Fix some formatting in buf_buddy_free_low() and buf_page_init_for_read().
uncompressed page frames.
buf_page_get_zip(), buf_page_release_zip(): New functions, used
by btr_copy_zblob_prefix().
btr_copy_zblob_prefix(): Do not call inflateEnd().
buf_LRU_free_block(): Do not allocate the control block when
a compressed-only page is being freed.
buf_validate(): Note that buf_pool->zip_clean may contain blocks
with io_fix == BUF_IO_READ.
btr_blob_free(): New function to commit a mini-transaction and to free
an uncompressed BLOB block, or the entire block.
btr_store_big_rec_extern_fields(): Replace the existing code with
btr_blob_free(). The old code may have contained a race condition.
btr_free_externally_stored_field(): Completely free the buffer blocks
allocated for the freed BLOB.
buf_page_get_gen(). This saves one mutex operation per block request.
buf_page_get_gen(), various macros and functions: Add parameter zip_size.
btr_node_ptr_get_child(): Add parameter index.
fil_space_get_latch(): Add optional output parameter zip_size.
fil_space_get_zip_size(): Return 0 for space id==0, because the
system tablespace is never compressed.
fsp_header_init(): Remove the parameter zip_size.
ibuf_free_excess_pages(): Remove the parameter zip_size.
trx_rseg_t, trx_undo_t: Add field zip_size.
xdes_lst_get_next(): Remove, unused.
Split the code to subroutines.
btr_copy_blob_prefix(): New function: copy the prefix of the externally
stored part of an uncompressed BLOB.
btr_copy_zblob_prefix(): New function: copy the prefix of the externally
stored part of a compressed BLOB.
btr_blob_get_part_len(), btr_blob_get_next_page_no(): Add const qualifier
to the parameter.
that also exists in uncompressed form in the buffer pool, pass the
compressed frame to fil_io() instead of the uncompressed one when
not using the doublewrite buffer.
page checksum of compressed-only blocks. Pass the compressed page frame
to fil_io() when needed.
page_zip_calc_checksum(): Skip also FIL_PAGE_LSN and FIL_PAGE_FILE_FLUSH_LSN.
buf_flush_init_for_writing(): Expect page to be non-NULL.
and to be flushed to disk.
buf_LRU_free_block(): Enable the freeing of uncompressed pages of
compressed tablespaces.
trx_doublewrite->buf_block_arr[]: Change the type from buf_block_t*
to buf_page_t*.
buf_flush_ready_for_flush(): Add debug assertion.
buf_flush_buffered_writes(), buf_flush_try_page(): Support blocks of type
BUF_BLOCK_ZIP_DIRTY.
buf_flush_post_to_doublewrite_buf(), buf_flush_write_block_low():
Change the type of the parameter from buf_block_t* to buf_page_t*.
buf_flush_init_for_writing(): Allow page to be NULL if page_zip_ is non-NULL.
compressed page) is not protected by block_mutex. Before releasing
buf_pool->mutex, we can simply assign b->io_fix. After reacquiring
buf_pool->mutex, we also have to acquire buf_pool->zip_mutex.
of a block, do not release buf_pool->mutex between the time the old control
block is removed from buf_pool->page_hash and the new control block is
added to it. Prevent operations on the compressed-only block while calling
btr_search_drop_page_hash_index() or page_zip_calc_checksum().
buf_LRU_invalidate_tablespace(): Revert the change done in r1223.
buf_pool->zip_mutex will have been released by
buf_LRU_block_remove_hashed_page() when it returns BUF_BLOCK_ZIP_FREE.
invoking buf_buddy_alloc(). An IO-fixed block must also be x-latched
when block->mutex and buf_pool->mutex are released.
buf_page_create(): Protect the block during buf_buddy_alloc() by
IO-fixing and X-latching it.
buf_zip_decompress(). This will prevent btr_cur_search_to_nth_level()
from accessing a half-decompressed leaf page. Internal B-tree nodes
(non-leaf pages) in B-tree searches are only protected by the tree
latch (index->lock) and by buffer-fixing.
buf_pool->page_hash and buf_pool->LRU before releasing buf_pool->mutex.
buf_page_init_for_read(), buf_page_create(): Allocate the compressed
page after the block has been added to the buffer pool. Document the
reason for this.
