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On reflection, filesize limit ought to be an exact power

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of 2 to save a few cycles in md.c.  So, make it 2^30 not 10^9.
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Tom Lane 1999-04-06 03:04:22 +00:00
parent 5ce851dcda
commit 5763683ce4
1 changed files with 7 additions and 6 deletions
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13
src/include/config.h.in
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@ -32,17 +32,18 @@
* Thus, the maximum size of a single file is RELSEG_SIZE * BLCKSZ;
* relations bigger than that are divided into multiple files.
*
* CAUTION: RELSEG_SIZE * BLCKSZ must be less than your OS' limit on file size.
* This is typically 2Gb or 4Gb in a 32-bit operating system. By default,
* we make the limit one billion bytes to avoid any possible integer-overflow
* CAUTION: RELSEG_SIZE * BLCKSZ must be less than your OS' limit on file
* size. This is typically 2Gb or 4Gb in a 32-bit operating system. By
* default, we make the limit 1Gb to avoid any possible integer-overflow
* problems within the OS. A limit smaller than necessary only means we
* divide a large relation into more chunks than necessary, so it seems best
* to err in the direction of a small limit.
* divide a large relation into more chunks than necessary, so it seems
* best to err in the direction of a small limit. (Besides, a power-of-2
* value saves a few cycles in md.c.)
*
* CAUTION: you had best do an initdb if you change either BLCKSZ or
* RELSEG_SIZE.
*/
#define RELSEG_SIZE (1000000000 / BLCKSZ)
#define RELSEG_SIZE (0x40000000 / BLCKSZ)
/*
* The following is set using configure.