Skip to content

More accurate calculation of the average page fill factor #8816

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 2 commits into from
Dec 1, 2025
Merged

More accurate calculation of the average page fill factor #8816

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
9839f81
More accurate (methinks) calculation of the average page fill factor
dyemanov Nov 29, 2025
2682f4e
Correction
dyemanov Dec 1, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
10 changes: 6 additions & 4 deletions src/utilities/gstat/dba.epp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1072,9 +1072,10 @@ int gstat(Firebird::UtilSvc* uSvc)
uSvc->printf(false, " Pointer pages: %ld, data page slots: %ld\n",
relation->rel_pointer_pages, relation->rel_slots);

const double average = (relation->rel_data_pages) ?
const auto nonEmptyPages = relation->rel_data_pages - relation->rel_empty_pages;
const double average = nonEmptyPages ?
(double) relation->rel_total_space * 100 /
((double) relation->rel_data_pages * (tddba->page_size - DPG_SIZE)) : 0.0;
((double) nonEmptyPages * (tddba->page_size - DPG_SIZE)) : 0.0;
uSvc->printf(false, " Data pages: %ld, average fill: %.0f%%\n",
relation->rel_data_pages, average);

Expand Down Expand Up @@ -1379,7 +1380,6 @@ static void analyze_data( dba_rel* relation, bool sw_record)
++relation->rel_slots;
if (*ptr)
{
++relation->rel_data_pages;
if (!analyze_data_page(relation, (const data_page*) db_read(*ptr), sw_record))
{
dba_print(false, 18, SafeArg() << *ptr);
Expand Down Expand Up @@ -1419,6 +1419,8 @@ static bool analyze_data_page( dba_rel* relation, const data_page* page, bool sw
if (page->dpg_header.pag_type != pag_data)
return false;

++relation->rel_data_pages;

if (sw_record)
{
memcpy(tddba->buffer2, (const SCHAR*) page, tddba->page_size);
Expand All @@ -1432,7 +1434,7 @@ static bool analyze_data_page( dba_rel* relation, const data_page* page, bool sw
{
if (tail->dpg_offset && tail->dpg_length)
{
space += tail->dpg_length;
space += FB_ALIGN(tail->dpg_length, ODS_ALIGNMENT);

if (sw_record)
{
Expand Down
Loading