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-- postgres 17.5

INFO:  vacuuming "ib.public.sbtest1"
INFO:  launched 0 parallel vacuum workers for index vacuuming (planned: 1)
INFO:  finished vacuuming "ib.public.sbtest1": index scans: 1
pages: 0 removed, 298234 remain, 298058 scanned (99.94% of total)
tuples: 10624 removed, 10004525 remain, 0 are dead but not yet removable
removable cutoff: 1450147223, which was 1 XIDs old when operation ended
frozen: 2889 pages from table (0.97% of total) had 86232 tuples frozen
index scan needed: 132758 pages from table (44.51% of total) had 170893 dead item identifiers removed

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--- postgres 17.6

pg_vac starts at Mon Aug  4 01:41:58 AM UTC 2025 with sleep_secs = 110
nr is :: 50000000 :: and ntabs is :: 1 ::
vac_args is (verbose, analyze, index_cleanup ON)
After load: wait for vacuum 0
Checkpoint started at Mon Aug  4 01:42:12 AM UTC 2025
CHECKPOINT
Checkpoint done at Mon Aug  4 01:42:26 AM UTC 2025
Sleep 82

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** Compaction Stats [default] **
Level    Files   Size     Score Read(GB)  Rn(GB) Rnp1(GB) Write(GB) Wnew(GB) Moved(GB) W-Amp Rd(MB/s) Wr(MB/s) Comp(sec) CompMergeCPU(sec) Comp(cnt) Avg(sec) KeyIn KeyDrop Rblob(GB) Wblob(GB)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  L0      0/0    0.00 KB   0.0     10.3     0.0     10.3      61.9     51.7       0.0   1.2     54.8    331.0    191.65            112.61      3598    0.053     25M   7102       0.0       0.0
  L3      4/0   59.79 MB   0.9    147.4    51.7     95.7     147.2     51.6       0.0   2.8    384.9    384.5    392.18            275.78       470    0.834    368M   286K       0.0       0.0
  L4     11/0   154.73 MB   0.9     98.6    47.9     50.6      98.3     47.7       3.6   2.1    337.2    336.5    299.29            182.77      2990    0.100    246M   472K       0.0       0.0
  L5    102/0    1.35 GB   1.

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v6.0.2
    16.83%  db_bench  db_bench.v6.0.2     [.] rocksdb::IndexBlockIter::Seek
    14.69%  db_bench  db_bench.v6.0.2     [.] rocksdb::DataBlockIter::Seek
    11.14%  db_bench  db_bench.v6.0.2     [.] rocksdb::LRUHandleTable::FindPointer
     6.67%  db_bench  libc-2.31.so        [.] __memcmp_avx2_movbe
     3.98%  db_bench  db_bench.v6.0.2     [.] rocksdb::Block::NewIterator<rocksdb::DataBlockIter>
     3.66%  db_bench  db_bench.v6.0.2     [.] rocksdb::LRUCacheShard::Lookup
     3.51%  db_bench  db_bench.v6.0.2     [.] rocksdb::(anonymous namespace)::FullFilterBitsReader::MayMatch
     3.13%  db_bench  db_bench.v6.0.2     [.] rocksdb::(anonymous namespace)::BytewiseComparatorImpl::Compare
     2.94%  db_bench  libpthread-2.31.so  [.] __pthread_mutex_unlock

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diff tools/db_bench_tool.cc db_bench_tool.cc.fillseq
--- tools/db_bench_tool.cc      2022-02-15 10:42:01.071748970 -0800
+++ db_bench_tool.cc.fillseq    2022-02-14 14:33:55.101778301 -0800
@@ -3115,6 +3115,7 @@
       if (port::kLittleEndian) {
         for (int i = 0; i < bytes_to_fill; ++i) {
           pos[i] = (prefix >> ((bytes_to_fill - i - 1) << 3)) & 0xFF;
+          printf("shift %d for i=%d to %ld\n",  ((bytes_to_fill - i - 1) << 3), i, (prefix >> ((bytes_to_fill - i - 1) << 3)));
         }
       } else {

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diff --git a/db/version_set.cc b/db/version_set.cc
index 5d9adf4b3..dc7f58695 100644
--- a/db/version_set.cc
+++ b/db/version_set.cc
@@ -3721,11 +3721,40 @@ void VersionStorageInfo::CalculateBaseBytes(const ImmutableOptions& ioptions,
         l0_size += f->fd.GetFileSize();
       }

-      uint64_t base_bytes_max =
-          std::max(options.max_bytes_for_level_base, l0_size);

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# ops_sec - operations per second
# mb_sec - ops_sec * size-of-operation-in-MB
# db_size - database size
# c_wgb - GB written by compaction
# w_amp - Write-amplification as (bytes written by compaction / bytes written by memtable flush)
# c_mbps - Average write rate for compaction
# c_secs - Wall clock seconds doing compaction
# usec_op - Microseconds per operation
# p50, p99, p99.9, p99.99 - 50th, 99th, 99.9th, 99.99th percentile response time in usecs
# pmax - max response time in usecs

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point-query.warm.range100.pk1
--- absolute
cpu/o		r/o	rKB/o	wKB/o	o/s	dbms
0.000362	0.003	0.248	1.33	74892	x.pg124.x5.pk1
0.000343	0.003	0.311	1.22	84139	x.pg134.x5.pk1
0.000326	0.003	0.322	1.223	84370	x.pg140.x5.pk1
--- relative to first result
0.95		1.00	1.25	0.92	1.12	x.pg134.x5.pk1
0.90		1.00	1.30	0.92	1.13	x.pg140.x5.pk1

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db_1 =  x.pg124.x5.pk1
db_2 =  x.pg134.x5.pk1
db_3 =  x.pg140.x5.pk1

db_1    db_2    db_3
1.00    1.12    1.13    point-query.warm.range100.pk1
1.00    0.99    1.05    point-query.pre.range100.pk1
1.00    1.00    1.02    random-points.pre.range10.pk1
1.00    1.00    1.02    random-points.pre.range100.pk1
1.00    1.00    1.00    random-points.pre.range1000.pk1

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point-query.warm.range100.pk1
--- absolute
cpu/o		r/o	rKB/o	wKB/o	o/s	dbms
0.000361	0.003	0.248	1.33	75046	x.pg124.x5.pk1
0.000343	0.003	0.31	1.219	83857	x.pg134.x5.pk1
0.000325	0.003	0.325	1.222	84459	x.pg140.x5.pk1
--- relative to first result
0.95		1.00	1.25	0.92	1.12	x.pg134.x5.pk1
0.90		1.00	1.31	0.92	1.13	x.pg140.x5.pk1