fix the calculation of BPFileHeader::MAX_PAGE_NUM and BP_PAGE_DATA_SIZE

[1036-ce]

What problem were solved in this pull request?

Issue Number: close #563

Problem:

What is changed and how it works?

This PR addresses two inconsistencies in the buffer pool page layout calculations:

1. Fix MAX_PAGE_NUM Calculation in BPFileHeader

From:

static const int MAX_PAGE_NUM = (BP_PAGE_DATA_SIZE - sizeof(page_count) - sizeof(allocated_pages)) * 8;

To:

static const int MAX_PAGE_NUM = (BP_PAGE_DATA_SIZE - sizeof(buffer_pool_id) - sizeof(page_count) - sizeof(allocated_pages)) * 8;

2. Fix BP_PAGE_DATA_SIZE in page.h

From:

static constexpr const int BP_PAGE_DATA_SIZE = (BP_PAGE_SIZE - sizeof(PageNum) - sizeof(LSN) - sizeof(CheckSum));

To:

static constexpr const int BP_PAGE_DATA_SIZE = (BP_PAGE_SIZE - sizeof(LSN) - sizeof(CheckSum));

[CLAassistant]

All committers have signed the CLA.

[nautaa]

LGTM, thanks for your contribution, please resolve the failed ci.

[1036-ce]

The failed ci has been resolved

[nautaa]

thanks again, If you want to continue contributing to the miniob/oceanbase community feel free to get in touch.