/*------------------------------------------------------------------------- * * bufpage.h * Standard POSTGRES buffer page definitions. * * * Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * * src/include/storage/bufpage.h * *------------------------------------------------------------------------- */ #ifndef BUFPAGE_H #define BUFPAGE_H #include "access/xlogdefs.h" #include "storage/item.h" #include "storage/off.h" /* * A postgres disk page is an abstraction layered on top of a postgres * disk block (which is simply a unit of i/o, see block.h). * * specifically, while a disk block can be unformatted, a postgres * disk page is always a slotted page of the form: * * +----------------+---------------------------------+ * | PageHeaderData | linp1 linp2 linp3 ... | * +-----------+----+---------------------------------+ * | ... linpN | | * +-----------+--------------------------------------+ * | ^ pd_lower | * | | * | v pd_upper | * +-------------+------------------------------------+ * | | tupleN ... | * +-------------+------------------+-----------------+ * | ... tuple3 tuple2 tuple1 | "special space" | * +--------------------------------+-----------------+ * ^ pd_special * * a page is full when nothing can be added between pd_lower and * pd_upper. * * all blocks written out by an access method must be disk pages. * * EXCEPTIONS: * * obviously, a page is not formatted before it is initialized by * a call to PageInit. * * NOTES: * * linp1..N form an ItemId array. ItemPointers point into this array * rather than pointing directly to a tuple. Note that OffsetNumbers * conventionally start at 1, not 0. * * tuple1..N are added "backwards" on the page. because a tuple's * ItemPointer points to its ItemId entry rather than its actual * byte-offset position, tuples can be physically shuffled on a page * whenever the need arises. * * AM-generic per-page information is kept in PageHeaderData. * * AM-specific per-page data (if any) is kept in the area marked "special * space"; each AM has an "opaque" structure defined somewhere that is * stored as the page trailer. an access method should always * initialize its pages with PageInit and then set its own opaque * fields. */ typedef Pointer Page; /* * location (byte offset) within a page. * * note that this is actually limited to 2^15 because we have limited * ItemIdData.lp_off and ItemIdData.lp_len to 15 bits (see itemid.h). */ typedef uint16 LocationIndex; /* * disk page organization * * space management information generic to any page * * pd_lsn - identifies xlog record for last change to this page. * pd_tli - ditto. * pd_flags - flag bits. * pd_lower - offset to start of free space. * pd_upper - offset to end of free space. * pd_special - offset to start of special space. * pd_pagesize_version - size in bytes and page layout version number. * pd_prune_xid - oldest XID among potentially prunable tuples on page. * * The LSN is used by the buffer manager to enforce the basic rule of WAL: * "thou shalt write xlog before data". A dirty buffer cannot be dumped * to disk until xlog has been flushed at least as far as the page's LSN. * We also store the 16 least significant bits of the TLI for identification * purposes (it is not clear that this is actually necessary, but it seems * like a good idea). * * pd_prune_xid is a hint field that helps determine whether pruning will be * useful. It is currently unused in index pages. * * The page version number and page size are packed together into a single * uint16 field. This is for historical reasons: before PostgreSQL 7.3, * there was no concept of a page version number, and doing it this way * lets us pretend that pre-7.3 databases have page version number zero. * We constrain page sizes to be multiples of 256, leaving the low eight * bits available for a version number. * * Minimum possible page size is perhaps 64B to fit page header, opaque space * and a minimal tuple; of course, in reality you want it much bigger, so * the constraint on pagesize mod 256 is not an important restriction. * On the high end, we can only support pages up to 32KB because lp_off/lp_len * are 15 bits. */ typedef struct PageHeaderData { /* XXX LSN is member of *any* block, not only page-organized ones */ XLogRecPtr pd_lsn; /* LSN: next byte after last byte of xlog * record for last change to this page */ uint16 pd_tli; /* least significant bits of the TimeLineID * containing the LSN */ uint16 pd_flags; /* flag bits, see below */ LocationIndex pd_lower; /* offset to start of free space */ LocationIndex pd_upper; /* offset to end of free space */ LocationIndex pd_special; /* offset to start of special space */ uint16 pd_pagesize_version; TransactionId pd_prune_xid; /* oldest prunable XID, or zero if none */ ItemIdData pd_linp[1]; /* beginning of line pointer array */ } PageHeaderData; typedef PageHeaderData *PageHeader; /* * pd_flags contains the following flag bits. Undefined bits are initialized * to zero and may be used in the future. * * PD_HAS_FREE_LINES is set if there are any LP_UNUSED line pointers before * pd_lower. This should be considered a hint rather than the truth, since * changes to it are not WAL-logged. * * PD_PAGE_FULL is set if an UPDATE doesn't find enough free space in the * page for its new tuple version; this suggests that a prune is needed. * Again, this is just a hint. */ #define PD_HAS_FREE_LINES 0x0001 /* are there any unused line pointers? */ #define PD_PAGE_FULL 0x0002 /* not enough free space for new * tuple? */ #define PD_ALL_VISIBLE 0x0004 /* all tuples on page are visible to * everyone */ #define PD_VALID_FLAG_BITS 0x0007 /* OR of all valid pd_flags bits */ /* * Page layout version number 0 is for pre-7.3 Postgres releases. * Releases 7.3 and 7.4 use 1, denoting a new HeapTupleHeader layout. * Release 8.0 uses 2; it changed the HeapTupleHeader layout again. * Release 8.1 uses 3; it redefined HeapTupleHeader infomask bits. * Release 8.3 uses 4; it changed the HeapTupleHeader layout again, and * added the pd_flags field (by stealing some bits from pd_tli), * as well as adding the pd_prune_xid field (which enlarges the header). */ #define PG_PAGE_LAYOUT_VERSION 4 /* ---------------------------------------------------------------- * page support macros * ---------------------------------------------------------------- */ /* * PageIsValid * True iff page is valid. */ #define PageIsValid(page) PointerIsValid(page) /* * line pointer(s) do not count as part of header */ #define SizeOfPageHeaderData (offsetof(PageHeaderData, pd_linp)) /* * PageIsEmpty * returns true iff no itemid has been allocated on the page */ #define PageIsEmpty(page) \ (((PageHeader) (page))->pd_lower <= SizeOfPageHeaderData) /* * PageIsNew * returns true iff page has not been initialized (by PageInit) */ #define PageIsNew(page) (((PageHeader) (page))->pd_upper == 0) /* * PageGetItemId * Returns an item identifier of a page. */ #define PageGetItemId(page, offsetNumber) \ ((ItemId) (&((PageHeader) (page))->pd_linp[(offsetNumber) - 1])) /* * PageGetContents * To be used in case the page does not contain item pointers. * * Note: prior to 8.3 this was not guaranteed to yield a MAXALIGN'd result. * Now it is. Beware of old code that might think the offset to the contents * is just SizeOfPageHeaderData rather than MAXALIGN(SizeOfPageHeaderData). */ #define PageGetContents(page) \ ((char *) (page) + MAXALIGN(SizeOfPageHeaderData)) /* ---------------- * macros to access page size info * ---------------- */ /* * PageSizeIsValid * True iff the page size is valid. */ #define PageSizeIsValid(pageSize) ((pageSize) == BLCKSZ) /* * PageGetPageSize * Returns the page size of a page. * * this can only be called on a formatted page (unlike * BufferGetPageSize, which can be called on an unformatted page). * however, it can be called on a page that is not stored in a buffer. */ #define PageGetPageSize(page) \ ((Size) (((PageHeader) (page))->pd_pagesize_version & (uint16) 0xFF00)) /* * PageGetPageLayoutVersion * Returns the page layout version of a page. */ #define PageGetPageLayoutVersion(page) \ (((PageHeader) (page))->pd_pagesize_version & 0x00FF) /* * PageSetPageSizeAndVersion * Sets the page size and page layout version number of a page. * * We could support setting these two values separately, but there's * no real need for it at the moment. */ #define PageSetPageSizeAndVersion(page, size, version) \ ( \ AssertMacro(((size) & 0xFF00) == (size)), \ AssertMacro(((version) & 0x00FF) == (version)), \ ((PageHeader) (page))->pd_pagesize_version = (size) | (version) \ ) /* ---------------- * page special data macros * ---------------- */ /* * PageGetSpecialSize * Returns size of special space on a page. */ #define PageGetSpecialSize(page) \ ((uint16) (PageGetPageSize(page) - ((PageHeader)(page))->pd_special)) /* * PageGetSpecialPointer * Returns pointer to special space on a page. */ #define PageGetSpecialPointer(page) \ ( \ AssertMacro(PageIsValid(page)), \ (char *) ((char *) (page) + ((PageHeader) (page))->pd_special) \ ) /* * PageGetItem * Retrieves an item on the given page. * * Note: * This does not change the status of any of the resources passed. * The semantics may change in the future. */ #define PageGetItem(page, itemId) \ ( \ AssertMacro(PageIsValid(page)), \ AssertMacro(ItemIdHasStorage(itemId)), \ (Item)(((char *)(page)) + ItemIdGetOffset(itemId)) \ ) /* * PageGetMaxOffsetNumber * Returns the maximum offset number used by the given page. * Since offset numbers are 1-based, this is also the number * of items on the page. * * NOTE: if the page is not initialized (pd_lower == 0), we must * return zero to ensure sane behavior. Accept double evaluation * of the argument so that we can ensure this. */ #define PageGetMaxOffsetNumber(page) \ (((PageHeader) (page))->pd_lower <= SizeOfPageHeaderData ? 0 : \ ((((PageHeader) (page))->pd_lower - SizeOfPageHeaderData) \ / sizeof(ItemIdData))) /* * Additional macros for access to page headers */ #define PageGetLSN(page) \ (((PageHeader) (page))->pd_lsn) #define PageSetLSN(page, lsn) \ (((PageHeader) (page))->pd_lsn = (lsn)) /* NOTE: only the 16 least significant bits are stored */ #define PageGetTLI(page) \ (((PageHeader) (page))->pd_tli) #define PageSetTLI(page, tli) \ (((PageHeader) (page))->pd_tli = (uint16) (tli)) #define PageHasFreeLinePointers(page) \ (((PageHeader) (page))->pd_flags & PD_HAS_FREE_LINES) #define PageSetHasFreeLinePointers(page) \ (((PageHeader) (page))->pd_flags |= PD_HAS_FREE_LINES) #define PageClearHasFreeLinePointers(page) \ (((PageHeader) (page))->pd_flags &= ~PD_HAS_FREE_LINES) #define PageIsFull(page) \ (((PageHeader) (page))->pd_flags & PD_PAGE_FULL) #define PageSetFull(page) \ (((PageHeader) (page))->pd_flags |= PD_PAGE_FULL) #define PageClearFull(page) \ (((PageHeader) (page))->pd_flags &= ~PD_PAGE_FULL) #define PageIsAllVisible(page) \ (((PageHeader) (page))->pd_flags & PD_ALL_VISIBLE) #define PageSetAllVisible(page) \ (((PageHeader) (page))->pd_flags |= PD_ALL_VISIBLE) #define PageClearAllVisible(page) \ (((PageHeader) (page))->pd_flags &= ~PD_ALL_VISIBLE) #define PageIsPrunable(page, oldestxmin) \ ( \ AssertMacro(TransactionIdIsNormal(oldestxmin)), \ TransactionIdIsValid(((PageHeader) (page))->pd_prune_xid) && \ TransactionIdPrecedes(((PageHeader) (page))->pd_prune_xid, oldestxmin) \ ) #define PageSetPrunable(page, xid) \ do { \ Assert(TransactionIdIsNormal(xid)); \ if (!TransactionIdIsValid(((PageHeader) (page))->pd_prune_xid) || \ TransactionIdPrecedes(xid, ((PageHeader) (page))->pd_prune_xid)) \ ((PageHeader) (page))->pd_prune_xid = (xid); \ } while (0) #define PageClearPrunable(page) \ (((PageHeader) (page))->pd_prune_xid = InvalidTransactionId) /* ---------------------------------------------------------------- * extern declarations * ---------------------------------------------------------------- */ extern void PageInit(Page page, Size pageSize, Size specialSize); extern bool PageHeaderIsValid(PageHeader page); extern OffsetNumber PageAddItem(Page page, Item item, Size size, OffsetNumber offsetNumber, bool overwrite, bool is_heap); extern Page PageGetTempPage(Page page); extern Page PageGetTempPageCopy(Page page); extern Page PageGetTempPageCopySpecial(Page page); extern void PageRestoreTempPage(Page tempPage, Page oldPage); extern void PageRepairFragmentation(Page page); extern Size PageGetFreeSpace(Page page); extern Size PageGetExactFreeSpace(Page page); extern Size PageGetHeapFreeSpace(Page page); extern void PageIndexTupleDelete(Page page, OffsetNumber offset); extern void PageIndexMultiDelete(Page page, OffsetNumber *itemnos, int nitems); #endif /* BUFPAGE_H */

RE-INVENTING THE TELEVISION NEWS BUSINESS*

A revolution in video storytelling

Creating entirely new & cost-effective production methods

From the world leaders in video production training and the creators of Character Driven Storytelling™

*and every other business that uses video

WHAT WE DO

Over the past 35 years, we have designed, built or restructured some of the most powerful news and journalism companies in the world.

We replace the traditional TV news ‘crew’ with one highly trained journalist, working alone with nothing but an iPhone.

No more TV news ‘crews’, no editors and no field producers.

This is television news done the way newspaper journalism is done – one reporter with their electronic pad and pencil.

In doing this, we can cut the cost of production by as much as 75% while increasing ratings and audience engagement.

In the place of conventional TV news ‘packages’ – ie, reporter stand up, interview, b-roll, man on the street, we marry great journalism with Netflix and Hollywood storytelling.

It’s a combination that works.

We have taken most of our clients to #1 in their respective markets.

And it’s not just for news. Any company, any profit, any NGO and anyone else who is online needs to tell their story in compelling yet cost-effective video. We can teach you to do that. Either in person or virtually.

EXAMPLES OF WHAT WE CAN TEACH YOUR STAFF TO PRODUCE

ITAY HOD

Itay Hod, MMJ with KPIX/CBS in San Francisco, took the 5-Day Intensive Video Storytelling Bootcamp in 2018.

Because he works alone, with only an iPhone, he was able to embed himself with a homeless family.

Here’s the story he produced in a one-day turn.

KIET DO

Kiet Do, an MMJ with KPIX/CBS in San Francisco, took the 5-Day Intensive Video Storytelling Bootcamp in 2021.

Here is a story he produced, all on his own, with only an iPhone and in a one-day turn.

TAYLOR SCHAUB

Taylor Schaub, an MMJ with Spectrum News 1 in LA, took the 5-Day Intensive Video Storytelling Bootcamp in 2023.

Here is a story he turned in only one day, using only an iPhone. It was the first video story he ever did and it was nominated for an Emmy.

THE BOOTCAMP

How do we convert stations and whole networks to working in this way?

Since 1988, we have run intensive 5-Day Video Storytelling Bootcamps

We have done these all over the world.

These are hands-on bootcamps, and participants learn an entirely new way of creating TV news stories.

-We shoot at a 3:1 ratio or lower, so turnaround times are fast.

-We go directly from camera to timelilne and edit – no written scripts. We work in the medium of pictures and sound.

-We are entirely character-driven.

-We are driven by pictures and real events.

-We are focused almost entirely on ’the viewer experience’.

Since 1988, more than 70,000 journalists around the world have taken our bootcamps, either in person on virtualy.

Case Studies

CBS News

We have started to work with CBS News, bringing our ideas of character-driven storytelling to one of the most successful and biggest networks in the United States. Since beginning to work with them ratings have climbed and more importantly, audience engagement is through the ceiling.

Learn More

New York Times Television

We started New York Times Television in 1990 and it was the first paper to be brought into the world of TV. It quickly became one of the most successful non-fiction production companies in the United States. The series and documentaries we produced won many awards including multiple Emmys.

Learn More

The BBC

We have been working with the BBC since the year 2000 helping to convert their national news network to our visual storytelling technique. Most recently we have trained teams from their sports, documentaries, and comedy divisions to make character-driven stories using only smartphones.

Learn More

Spectrum News

For the past five years we have worked with Spectrum News to introduce and train their journalists on visual, character driven storytelling using smartphones helping to create a different kind of local news for their network of 24-Hour News Stations across the United States.

Learn More

The United Nations

In 2006, we were approached by the United Nations. Rather than rely on news outlets, it would be much easier to train the field operatives to produce their own stories. We spent two years working with the UN, training more than 100 of their staff in bootcamps in Geneva and Nairobi.

Learn More

The Newark Star-Ledger

We trained 50 print reporters at the paper to shoot and tell their own stories, in conjunction with their print work. We built a TV newsroom in their existing print newsroom – you could not ask for a better set and they began to live stream their stories in conjunction with their print work.

Learn More

Mcgraw Hill

We spent two years with McGraw Hill, training more than 150 of their staffers, making them completely video literate. McGraw/Hill media properties we transit included Business Week, Aviation Week, (what was the name of the architecture magazine), and JD Power and Associates.

Learn More

Voice of America

In 1990, we were approached by The Voice of America, the official broadcasting agency for the United States Government. When we met with VOA, they were only a short wave radio broadcaster, but working with them, we took them into television, launching VOA-TV.

Learn More

Oyster Yachts

British based Oyster Yachts makes some of the finest yachts in the world. Like every other company, they had to find a way to feed the never-ending video demands of social media – sites like Instagram and TikTok. We trained the Oyster staff to tell their own stories, using only iPhones.

Learn More

Scottish Environmental Protection Agency

We were approached by SEPA, the Scottish Environmental Protection Agency because they had to continually find a way to ‘feed the media beast’. The result was that SEPA was able to tell their own stories, whenever they wanted, and at almost no additional cost.

Learn More

Michael on Media

Michael Rosenblum has been writing about the media since 1988. His work and ideas have appeared in The Guardian, The Huffington Post, Ilkeston Life and many other publications.

He has been blogging regularly for the past 35 years on this subject. Having taught media studies at Columbia University, NYU and now the University of Oxford, he is considered an expert on this subject.

Continue reading this post or look back at previous posts.

Do You Have Questions About Learning Video Skills?

If you would like to know more about our courses contact us and one of our training advisors will be happy to call you.

Your IP : 216.73.216.103

RE-INVENTING THE TELEVISION NEWS BUSINESS*

A revolution in video storytelling

Creating entirely new & cost-effective production methods

From the world leaders in video production training and the creators of Character Driven Storytelling™

*and every other business that uses video

WHAT WE DO

Over the past 35 years, we have designed, built or restructured some of the most powerful news and journalism companies in the world.

We replace the traditional TV news ‘crew’ with one highly trained journalist, working alone with nothing but an iPhone.

No more TV news ‘crews’, no editors and no field producers.

This is television news done the way newspaper journalism is done – one reporter with their electronic pad and pencil.

In doing this, we can cut the cost of production by as much as 75% while increasing ratings and audience engagement.

In the place of conventional TV news ‘packages’ – ie, reporter stand up, interview, b-roll, man on the street, we marry great journalism with Netflix and Hollywood storytelling.

It’s a combination that works.

We have taken most of our clients to #1 in their respective markets.

And it’s not just for news. Any company, any profit, any NGO and anyone else who is online needs to tell their story in compelling yet cost-effective video. We can teach you to do that. Either in person or virtually.

EXAMPLES OF WHAT WE CAN TEACH YOUR STAFF TO PRODUCE

ITAY HOD

Itay Hod, MMJ with KPIX/CBS in San Francisco, took the 5-Day Intensive Video Storytelling Bootcamp in 2018.

Because he works alone, with only an iPhone, he was able to embed himself with a homeless family.

Here’s the story he produced in a one-day turn.

KIET DO

Kiet Do, an MMJ with KPIX/CBS in San Francisco, took the 5-Day Intensive Video Storytelling Bootcamp in 2021.

Here is a story he produced, all on his own, with only an iPhone and in a one-day turn.

TAYLOR SCHAUB

Taylor Schaub, an MMJ with Spectrum News 1 in LA, took the 5-Day Intensive Video Storytelling Bootcamp in 2023.

Here is a story he turned in only one day, using only an iPhone. It was the first video story he ever did and it was nominated for an Emmy.

THE BOOTCAMP

How do we convert stations and whole networks to working in this way?

Since 1988, we have run intensive 5-Day Video Storytelling Bootcamps

We have done these all over the world.

These are hands-on bootcamps, and participants learn an entirely new way of creating TV news stories.

-We shoot at a 3:1 ratio or lower, so turnaround times are fast.

-We go directly from camera to timelilne and edit – no written scripts. We work in the medium of pictures and sound.

-We are entirely character-driven.

-We are driven by pictures and real events.

-We are focused almost entirely on ’the viewer experience’.

Since 1988, more than 70,000 journalists around the world have taken our bootcamps, either in person on virtualy.

Case Studies

CBS News

New York Times Television

The BBC

Spectrum News

The United Nations

The Newark Star-Ledger

Mcgraw Hill

Voice of America

Oyster Yachts

Scottish Environmental Protection Agency

Michael on Media