Implement a dynamically growing memory log buffer with an upper limit.

Implement a dynamically growing memory log buffer with an upper limit.

The goal of this change is to allow longer profiling sessions and preserve memory when profiler isn't started. The buffer starts with 64K and grows until it reaches the upper limit, which is currently set to 50MB --- according to my evaluations, this is enough for at least 20 minutes of GMail profiling. As we're planning to introduce compression for the profiler log, this time boundary will be significantly increased soon.

To make possible unit testing of the new component, I've factored out Logger's utility classes into a separate source file: log-utils.h/cc. Log and LogMessageBuilder are moved there from log.cc without any semantical changes.

Committed: http://code.google.com/p/v8/source/detail?r=2067

[Søren Thygesen Gjesse, 2009-05-27 12:00:40]

LGTM

http://codereview.chromium.org/115814/diff/1/3
File src/log-utils.cc (right):

http://codereview.chromium.org/115814/diff/1/3#newcode43
Line 43: blocks_[0] = NewArray<char>(block_size_);
Maybe add a private method AllocateBlock.

http://codereview.chromium.org/115814/diff/1/3#newcode93
Line 93: blocks_[++block_index_] = NewArray<char>(block_size_);
Ditto.

http://codereview.chromium.org/115814/diff/1/4
File src/log-utils.h (right):

http://codereview.chromium.org/115814/diff/1/4#newcode49
Line 49: // filled is returned, it is <= that 'buf_size'.
Remove that

http://codereview.chromium.org/115814/diff/1/7
File test/cctest/test-log-utils.cc (right):

http://codereview.chromium.org/115814/diff/1/7#newcode16
Line 16: // Writes ref_buffer.length chars into dynabuf.
Please add to comment that this also actually fills the ref_buffer before
writing it to the dynabuf.

[Mikhail Naganov, 2009-05-28 07:05:35]

http://codereview.chromium.org/115814/diff/1/3
File src/log-utils.cc (right):

http://codereview.chromium.org/115814/diff/1/3#newcode43
Line 43: blocks_[0] = NewArray<char>(block_size_);
On 2009/05/27 12:00:40, Søren Gjesse wrote:
> Maybe add a private method AllocateBlock.

Done.

http://codereview.chromium.org/115814/diff/1/3#newcode93
Line 93: blocks_[++block_index_] = NewArray<char>(block_size_);
On 2009/05/27 12:00:40, Søren Gjesse wrote:
> Ditto.

Done.

http://codereview.chromium.org/115814/diff/1/4
File src/log-utils.h (right):

http://codereview.chromium.org/115814/diff/1/4#newcode49
Line 49: // filled is returned, it is <= that 'buf_size'.
On 2009/05/27 12:00:40, Søren Gjesse wrote:
> Remove that

Done.

http://codereview.chromium.org/115814/diff/1/7
File test/cctest/test-log-utils.cc (right):

http://codereview.chromium.org/115814/diff/1/7#newcode16
Line 16: // Writes ref_buffer.length chars into dynabuf.
On 2009/05/27 12:00:40, Søren Gjesse wrote:
> Please add to comment that this also actually fills the ref_buffer before
> writing it to the dynabuf.

Done.