SqlScan's prior design called hbrt.MakeArrayFrom per matching row,
each one allocating a fresh &HbArray{}. For 50k rows that's 50k tiny
Go heap allocations + GC pressure that the flat-backing-buffer work
from 85541a3 left untouched (that commit eliminated the per-row items
slice alloc but not the header alloc).
hbrt.ArraySlab pre-allocates a `[]HbArray` slab of the estimated row
count and hands out `&slab.buf[idx]` on each WrapNext. One underlying
make() replaces N; pointers stay stable because slab growth reallocates
a fresh buffer instead of reusing the old one, so previously-handed-out
pointers remain valid (the old backing is kept alive by the references).
API kept tiny:
slab := hbrt.NewArraySlab(estRows)
val := slab.WrapNext(items) // returns Value wrapping &slab.buf[i]
SqlScan now pairs this with the existing flat value buffer for a
single-allocation-per-chunk scan hot loop.
Combined bench impact (50k rows, steady state):
Session start Now
no WHERE 14.6ms 9.2ms ← 1.3x vs raw RDD baseline
numeric WHERE 11.7ms 10.2ms
string WHERE 10.5ms 10.5ms
raw RDD baseline 6.8ms 7.0ms
no WHERE is now within 30% of raw RDD. Remaining gap is largely
Area.GetValue boxing overhead and the pcode opcode dispatch loop
itself — no further structural wins without a wider refactor.
Validation:
- FiveSql2 43/43
- Harbour compat 51/51
- go test ./... ALL PASS
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
From senior Go developer review:
C7 CRITICAL: pagePool data race (ntx.go)
- Moved global pagePool[8] + pagePoolIdx into per-Index struct
- Eliminates race condition across goroutines using separate indexes
C8 CRITICAL: Page.data dangling pointer after remap (ntx.go)
- remapFile() now clears pagePool data slices (pointed into old mmap)
- Prevents segfault from stale mmap references
C4 HIGH: pop() bounds check restored (thread.go)
- Removed performance optimization that eliminated underflow detection
- Stack underflow now produces clear error instead of index -1 panic
C1 HIGH: intExpLen overflow on MinInt64 (value.go)
- Added special case: MinInt64 returns 20 (length of -9223372036854775808)
- Prevents -v overflow in negation
C11 CRITICAL: GoTo ReadAt error handling (dbf.go)
- ReadAt failure now returns error and sets EOF
- Previously silently used stale record buffer (data corruption risk)
C14 HIGH: LEN() inline missing Hash case (gengo.go)
- Added _v.IsHash() → len(Keys) branch
C15 HIGH: EMPTY() inline missing Date case (gengo.go)
- Added _v.IsDate() && _v.AsJulian() == 0 check
82/82 stress PASS. 14 packages ALL PASS.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
value.go:
- cachedNil, cachedTrue, cachedFalse: pre-built constant Values
- MakeBool()/MakeNil(): return cached (zero allocation)
- smallInts[256]: pre-built integers 0-255 (skip intExpLen loop)
- MakeInt(): fast path for 0-255
thread.go:
- pop(): use cachedNil for GC help (no MakeNil() call)
ops_compare.go:
- LessEqual(): inline Int-Int fast path (skip valueCompare)
Direct scalar comparison with cached bool result
- Not(): inline logical fast path (skip IsLogical+AsBool)
- PopLogical(): inline type check + scalar read
Impact: these functions called millions of times in FOR/DO WHILE loops.
10K SEEK: 20ms → 16ms (20%). CDX SCOPE: 12ms → 9ms (25%).
82/82 stress PASS. 14 packages ALL PASS.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
CDX Integration:
- IndexEngine interface: common for NTX Index and CDX Tag
- OrderListAdd: auto-detects .cdx/.ntx extension, opens CDX tags
- decodeCompoundLeaf: proper bit-packed tag directory decoding
(was stub falling through to scanCompoundLeaves with wrong names)
- CDX Tag: added KeyLen(), KeyExpr(), ForExpr(), IsDescending(), Close()
- CDX compound recNo = direct byte offset (not page number)
ORDSCOPE:
- SetScope/ClearScope/SetScopeTop/SetScopeBottom on DBFArea
- GoTopIndexed: seeks to scopeTop, validates within scopeBottom
- GoBottomIndexed: seeks to scopeBottom boundary
- SkipIndexed: stops at scope boundaries (top and bottom)
- OrdScope RTL function registered (nScope: 0=TOP, 1=BOTTOM)
- scopeKeyFromValue: converts Value to padded key bytes
Index Order Management:
- OrderListFocus: handles numeric order ("2" → order 2)
- SET ORDER TO n: gengo emits hbrt.NtoS for int-to-string conversion
- IndexOrd/OrdCount/OrdName/OrdKey: real implementations (were stubs)
- OrderCount/CurrentOrder/OrderName/OrderKeyExpr accessors on DBFArea
- ClearScope on order switch (prevents stale scope)
Cross-read test: Harbour-created CDX → Five reads, 20/20 items match:
NAME/CITY/ID seek, ORDSCOPE count, GoTop/GoBottom all identical
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Bug 1: FIELD->NAME in INDEX ON expression
- evalKeyExprInner: strip FIELD->/alias-> prefix before field lookup
- exprToString: handle AliasExpr (FIELD->NAME → "FIELD->NAME")
Bug 2: AsNumInt() on Double returned IEEE 754 raw bits
- Value.AsNumInt(): check tDouble and convert via Float64frombits
- Fixed array index crash when index is result of % modulo
Bug 3: PACK/ZAP crash with open indexes
- OrderListRebuild: fully implemented (was TODO stub)
Saves index info, closes all, sets idxState=nil, recreates
- OrderCreate: set current=-1 during key evaluation (natural GoTo)
- PACK/ZAP: save/restore idxState, rebuild after operation
- Register __DBPACK, __DBZAP, DBRECALL symbol aliases
Harbour vs Five: 45/47 match (96%), 2 diffs are duplicate-key sort order
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
