Tim Armstrong has posted comments on this change. Change subject: IMPALA-3201: buffer pool header only ......................................................................
Patch Set 7: (7 comments) http://gerrit.cloudera.org:8080/#/c/3688/7/be/src/bufferpool/buffer-pool.h File be/src/bufferpool/buffer-pool.h: PS7, Line 124: free up memory reservations > this instance wasn't updated to be clearer on terminology: Done Line 155: /// remainder will not be usable. > alternatively, express size as multiple of min_buffer_len My thought was that it was best to consistently denominate buffers in bytes rather than use two different units. There's a trade-off here in that we have to document what happens in this case, but I like the consistency. Line 201: /// closed and 'buffer_handle' will reference the buffer from 'page_handle'. This > "will be closed" = "will be destroyed", i assume? we seem to use close and The handle is closed and the page is destroyed. I'll use the second here since it's clearer. PS7, Line 217: frees > also not updated: Done Line 218: /// reservation in 'src_client'. 'src' must be open and 'dst' must be closed before > how do you get a closed BufferHandle, other than calling allocate and free The default constructor of BufferHandle creates a closed buffer handle: it's only opened by calling a buffer pool method with this as an argument. So the code looks like: BufferHandle dst; TransferBuffer(src_client, &src, dst_client, &dst); Line 218: /// reservation in 'src_client'. 'src' must be open and 'dst' must be closed before > we can decide to change this later, if the code that calls this ends up loo Sounds good. Line 279: const BufferHandle* buffer_handle() const; > presumably an error to call FreeBuffer on the returned handle directly? Right, that's what the const modifier is enforcing. Extended comment to explain it. -- To view, visit http://gerrit.cloudera.org:8080/3688 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-MessageType: comment Gerrit-Change-Id: Id771dea2eb4c1aa13c30d59e8b184a7d1bca8d34 Gerrit-PatchSet: 7 Gerrit-Project: Impala Gerrit-Branch: cdh5-trunk Gerrit-Owner: Tim Armstrong <[email protected]> Gerrit-Reviewer: Dan Hecht <[email protected]> Gerrit-Reviewer: Marcel Kornacker <[email protected]> Gerrit-Reviewer: Michael Ho Gerrit-Reviewer: Tim Armstrong <[email protected]> Gerrit-HasComments: Yes
