Before this CL:
$ go test -bench=CompressedZipGarbage -count=5 -run=NONE archive/zip
BenchmarkCompressedZipGarbage-8 50 20677087 ns/op 42973 B/op 47 allocs/op
BenchmarkCompressedZipGarbage-8 100 20584764 ns/op 24294 B/op 47 allocs/op
BenchmarkCompressedZipGarbage-8 50 20859221 ns/op 42973 B/op 47 allocs/op
BenchmarkCompressedZipGarbage-8 100 20901176 ns/op 24294 B/op 47 allocs/op
BenchmarkCompressedZipGarbage-8 50 21282409 ns/op 42973 B/op 47 allocs/op
The B/op number is effectively meaningless. There
is a surprisingly large one-time cost that gets
divided by the number of iterations that your
machine can get through in a second.
This CL discards the first run, which helps.
It is not a panacea. Running with -benchtime=10s
will allow the sync.Pool to be emptied,
which brings the problem back.
However, since there are more iterations to divide
the cost through, it’s not quite as bad,
and running with a high benchtime is rare.
This CL changes the meaning of the B/op number,
which is unfortunate, since it won’t have the
same order of magnitude as previous Go versions.
But it wasn’t really comparable before anyway,
since it didn’t have any reliable meaning at all.
After this CL:
$ go test -bench=CompressedZipGarbage -count=5 -run=NONE archive/zip
BenchmarkCompressedZipGarbage-8 100 20881890 ns/op 5616 B/op 47 allocs/op
BenchmarkCompressedZipGarbage-8 50 20622757 ns/op 5616 B/op 47 allocs/op
BenchmarkCompressedZipGarbage-8 50 20628193 ns/op 5616 B/op 47 allocs/op
BenchmarkCompressedZipGarbage-8 100 20756612 ns/op 5616 B/op 47 allocs/op
BenchmarkCompressedZipGarbage-8 100 20639774 ns/op 5616 B/op 47 allocs/op
Change-Id: Iedee04f39328974c7fa272a6113d423e7ffce50f
Reviewed-on: https://go-review.googlesource.com/22585
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
a new relocation R_ADDRMIPSTLS is added, which resolves to 16-bit offset
of a TLS address on mips64x.
Change-Id: Ic60d0e1ba49ff1c433cead242f5884677ab227a5
Reviewed-on: https://go-review.googlesource.com/19804
Reviewed-by: Minux Ma <minux@golang.org>
This updates some comments that became out of date when we moved the
mark bit out of the heap bitmap and started using the high bit for the
first word as a scan/dead bit.
Change-Id: I4a572d16db6114cadff006825466c1f18359f2db
Reviewed-on: https://go-review.googlesource.com/22662
Reviewed-by: Rick Hudson <rlh@golang.org>
MIPS N64 ABI passes arguments in registers R4-R11, return value in R2.
R16-R23, R28, R30 and F24-F31 are callee-save. gcc PIC code expects
to be called with indirect call through R25.
Change-Id: I24f582b4b58e1891ba9fd606509990f95cca8051
Reviewed-on: https://go-review.googlesource.com/19805
Reviewed-by: Minux Ma <minux@golang.org>
Factor out the Aux/AuxInt handling in (*Value).LongString() and
use it in (*Value).LongHTML() as well.
This especially improves readability of auxFloat32, auxFloat64,
and auxSymValAndOff values which would otherwise be printed as
opaque integers.
This change also makes LongString() slightly less verbose by
eliding offsets that are zero (as is very often the case).
Additionally, ensure the HTML is interpreted as UTF-8 so that
non-ASCII characters (especially the "middle dots" in some symbols)
show up correctly.
Change-Id: Ie26221df876faa056d322b3e423af63f33cd109d
Reviewed-on: https://go-review.googlesource.com/22641
Reviewed-by: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Frits van Bommel <fvbommel@gmail.com>
SB register (R28) is introduced for access external addresses with shorter
instruction sequences. It is loaded at entry points. External data within
2G of SB can be accessed this way.
cmd/internal/obj: relocaltion R_ADDRMIPS is split into two relocations
R_ADDRMIPS and R_ADDRMIPSU, handling the low 16 bits and the "upper" 16
bits of external addresses, respectively, since the instructios may not
be adjacent. It might be better if relocation Variant could be used.
cmd/link/internal/mips64: support new relocations.
cmd/compile/internal/mips64: reserve SB register.
runtime: initialize SB register at entry points.
Change-Id: I5f34868f88c5a9698c042a8a1f12f76806c187b9
Reviewed-on: https://go-review.googlesource.com/19802
Reviewed-by: Minux Ma <minux@golang.org>
Leave R28 to SB register, which will be introduced in CL 19802.
Change-Id: I1cf7a789695c5de664267ec8086bfb0b043ebc14
Reviewed-on: https://go-review.googlesource.com/19863
Reviewed-by: Minux Ma <minux@golang.org>
on mips64, address is 64 bit, not a WORD. also it is never used anywhere.
Change-Id: Ic6bf6d6a21c8d2f1eb7bfe9efc5a29186ec2a8ef
Reviewed-on: https://go-review.googlesource.com/19801
Reviewed-by: Minux Ma <minux@golang.org>
The HTTP client had a limit for the maximum number of idle connections
per-host, but not a global limit.
This CLs adds a global idle connection limit too,
Transport.MaxIdleConns.
All idle conns are now also stored in a doubly-linked list. When there
are too many, the oldest one is closed.
Fixes#15461
Change-Id: I72abbc28d140c73cf50f278fa70088b45ae0deef
Reviewed-on: https://go-review.googlesource.com/22655
Reviewed-by: Andrew Gerrand <adg@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Clarify that it includes the RFC 7230 "request-line".
Fixes#15494
Change-Id: I9cc5dd5f2d85ebf903229539208cec4da5c38d04
Reviewed-on: https://go-review.googlesource.com/22656
Reviewed-by: Andrew Gerrand <adg@golang.org>
Previously named byte types like json.RawMessage could get dirty
database memory from a call to Scan. These types would activate a
code path that didn't clone the byte data coming from the database
before assigning it. Another thread could then overwrite the byte
array in src, which has unexpected consequences.
Originally reported by Jason Moiron; the patch and test are his
suggestions. Fixes#13905.
Change-Id: Iacfef61cbc9dd51c8fccef9b2b9d9544c77dd0e0
Reviewed-on: https://go-review.googlesource.com/22393
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
With the switch to separate mark bitmaps, the scan/dead bit for the
first word of each object is now unused. Reclaim this bit and use it
as a scan/dead bit, just like words three and on. The second word is
still used for checkmark.
This dramatically simplifies heapBitsSetTypeNoScan and hasPointers,
since they no longer need different cases for 1, 2, and 3+ word
objects. They can instead just manipulate the heap bitmap for the
first word and be done with it.
In order to enable this, we change heapBitsSetType and runGCProg to
always set the scan/dead bit to scan for the first word on every code
path. Since these functions only apply to types that have pointers,
there's no need to do this conditionally: it's *always* necessary to
set the scan bit in the first word.
We also change every place that scans an object and checks if there
are more pointers. Rather than only checking morePointers if the word
is >= 2, we now check morePointers if word != 1 (since that's the
checkmark word).
Looking forward, we should probably reclaim the checkmark bit, too,
but that's going to be quite a bit more work.
Tested by setting doubleCheck in heapBitsSetType and running all.bash
on both linux/amd64 and linux/386, and by running GOGC=10 all.bash.
This particularly improves the FmtFprintf* go1 benchmarks, since they
do a large amount of noscan allocation.
name old time/op new time/op delta
BinaryTree17-12 2.34s ± 1% 2.38s ± 1% +1.70% (p=0.000 n=17+19)
Fannkuch11-12 2.09s ± 0% 2.09s ± 1% ~ (p=0.276 n=17+16)
FmtFprintfEmpty-12 44.9ns ± 2% 44.8ns ± 2% ~ (p=0.340 n=19+18)
FmtFprintfString-12 127ns ± 0% 125ns ± 0% -1.57% (p=0.000 n=16+15)
FmtFprintfInt-12 128ns ± 0% 122ns ± 1% -4.45% (p=0.000 n=15+20)
FmtFprintfIntInt-12 207ns ± 1% 193ns ± 0% -6.55% (p=0.000 n=19+14)
FmtFprintfPrefixedInt-12 197ns ± 1% 191ns ± 0% -2.93% (p=0.000 n=17+18)
FmtFprintfFloat-12 263ns ± 0% 248ns ± 1% -5.88% (p=0.000 n=15+19)
FmtManyArgs-12 794ns ± 0% 779ns ± 1% -1.90% (p=0.000 n=18+18)
GobDecode-12 7.14ms ± 2% 7.11ms ± 1% ~ (p=0.072 n=20+20)
GobEncode-12 5.85ms ± 1% 5.82ms ± 1% -0.49% (p=0.000 n=20+20)
Gzip-12 218ms ± 1% 215ms ± 1% -1.22% (p=0.000 n=19+19)
Gunzip-12 36.8ms ± 0% 36.7ms ± 0% -0.18% (p=0.006 n=18+20)
HTTPClientServer-12 77.1µs ± 4% 77.1µs ± 3% ~ (p=0.945 n=19+20)
JSONEncode-12 15.6ms ± 1% 15.9ms ± 1% +1.68% (p=0.000 n=18+20)
JSONDecode-12 55.2ms ± 1% 53.6ms ± 1% -2.93% (p=0.000 n=17+19)
Mandelbrot200-12 4.05ms ± 1% 4.05ms ± 0% ~ (p=0.306 n=17+17)
GoParse-12 3.14ms ± 1% 3.10ms ± 1% -1.31% (p=0.000 n=19+18)
RegexpMatchEasy0_32-12 69.3ns ± 1% 70.0ns ± 0% +0.89% (p=0.000 n=19+17)
RegexpMatchEasy0_1K-12 237ns ± 1% 236ns ± 0% -0.62% (p=0.000 n=19+16)
RegexpMatchEasy1_32-12 69.5ns ± 1% 70.3ns ± 1% +1.14% (p=0.000 n=18+17)
RegexpMatchEasy1_1K-12 377ns ± 1% 366ns ± 1% -3.03% (p=0.000 n=15+19)
RegexpMatchMedium_32-12 107ns ± 1% 107ns ± 2% ~ (p=0.318 n=20+19)
RegexpMatchMedium_1K-12 33.8µs ± 3% 33.5µs ± 1% -1.04% (p=0.001 n=20+19)
RegexpMatchHard_32-12 1.68µs ± 1% 1.73µs ± 0% +2.50% (p=0.000 n=20+18)
RegexpMatchHard_1K-12 50.8µs ± 1% 52.0µs ± 1% +2.50% (p=0.000 n=19+18)
Revcomp-12 381ms ± 1% 385ms ± 1% +1.00% (p=0.000 n=17+18)
Template-12 64.9ms ± 3% 62.6ms ± 1% -3.55% (p=0.000 n=19+18)
TimeParse-12 324ns ± 0% 328ns ± 1% +1.25% (p=0.000 n=18+18)
TimeFormat-12 345ns ± 0% 334ns ± 0% -3.31% (p=0.000 n=15+17)
[Geo mean] 52.1µs 51.5µs -1.00%
Change-Id: I13e74da3193a7f80794c654f944d1f0d60817049
Reviewed-on: https://go-review.googlesource.com/22632
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This makes this code better self-documenting and makes it easier to
find these places in the future.
Change-Id: I31dc5598ae67f937fb9ef26df92fd41d01e983c3
Reviewed-on: https://go-review.googlesource.com/22631
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
heapBits.bits is carefully written to produce good machine code. Use
it in heapBits.morePointers and heapBits.isPointer to get good machine
code there, too.
Change-Id: I208c7d0d38697e7a22cad67f692162589b75f1e2
Reviewed-on: https://go-review.googlesource.com/22630
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Fix issues introduced in 5f9a870.
Change-Id: Ia75945ef563956613bf88bbe57800a96455c265d
Reviewed-on: https://go-review.googlesource.com/22661
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Add support for the context function set by runtime.SetCgoTraceback.
The context function was added in CL 17761, without support.
This CL is the support.
This CL has not been tested for real C code, as a working context
function for C code requires unwind support that does not seem to exist.
I wanted to get the CL out before the freeze.
I apologize for the length of this CL. It's mostly plumbing, but
unfortunately the plumbing is processor-specific.
Change-Id: I8ce11a0de9b3dafcc29efd2649d776e93bff0e90
Reviewed-on: https://go-review.googlesource.com/22508
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This commit adds the new 'ctrAble' interface to the crypto/cipher
package. The role of ctrAble is the same as gcmAble but for CTR
instead of GCM. It allows block ciphers to provide optimized CTR
implementations.
The primary benefit of adding CTR support to the s390x AES
implementation is that it allows us to encrypt the counter values
in bulk, giving the cipher message instruction a larger chunk of
data to work on per invocation.
The xorBytes assembly is necessary because xorBytes becomes a
bottleneck when CTR is done in this way. Hopefully it will be
possible to remove this once s390x has migrated to the ssa
backend.
name old speed new speed delta
AESCTR1K 160MB/s ± 6% 867MB/s ± 0% +442.42% (p=0.000 n=9+10)
Change-Id: I1ae16b0ce0e2641d2bdc7d7eabc94dd35f6e9318
Reviewed-on: https://go-review.googlesource.com/22195
Reviewed-by: Adam Langley <agl@golang.org>
This commit adds the cbcEncAble and cbcDecAble interfaces that
can be implemented by block ciphers that support an optimized
implementation of CBC. This is similar to what is done for GCM
with the gcmAble interface.
The cbcEncAble, cbcDecAble and gcmAble interfaces all now have
tests to ensure they are detected correctly in the cipher
package.
name old speed new speed delta
AESCBCEncrypt1K 152MB/s ± 1% 1362MB/s ± 0% +795.59% (p=0.000 n=10+9)
AESCBCDecrypt1K 143MB/s ± 1% 1362MB/s ± 0% +853.00% (p=0.000 n=10+9)
Change-Id: I715f686ab3686b189a3dac02f86001178fa60580
Reviewed-on: https://go-review.googlesource.com/22523
Run-TryBot: Michael Munday <munday@ca.ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>
This commit moves the GC from free list allocation to
bit mark allocation. Instead of using the bitmaps
generated during the mark phases to generate free
list and then using the free lists for allocation we
allocate directly from the bitmaps.
The change in the garbage benchmark
name old time/op new time/op delta
XBenchGarbage-12 2.22ms ± 1% 2.13ms ± 1% -3.90% (p=0.000 n=18+18)
Change-Id: I17f57233336f0ca5ef5404c3be4ecb443ab622aa
nextFreeFast is currently not inlined by the compiler due
to its size and complexity. This CL simplifies
nextFreeFast by letting the slow path handle (nextFree)
handle a corner cases.
Change-Id: Ia9c5d1a7912bcb4bec072f5fd240f0e0bafb20e4
Reviewed-on: https://go-review.googlesource.com/22598
Reviewed-by: Austin Clements <austin@google.com>
Run-TryBot: Austin Clements <austin@google.com>
This is necessary to avoid disrupting the go1 suite and gives
us a place to put other tests of basic compiler function and
correctness.
Change-Id: I36933819ff2bfe6a2121fff2be9a98efd2123d9a
Reviewed-on: https://go-review.googlesource.com/22597
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Break really long lines.
Add spacing to line up columns.
In AMD64, put all the optimization rules after all the
lowering rules.
Change-Id: I45cc7368bf278416e67f89e74358db1bd4326a93
Reviewed-on: https://go-review.googlesource.com/22470
Reviewed-by: David Chase <drchase@google.com>
sweep used to skip mcental.freeSpan (and its locking) if it didn't
find any new free objects. We lost that optimization when the
freed-object counting changed in dad83f7 to count total free objects
instead of newly freed objects.
The previous commit brings back counting of newly freed objects, so we
can easily revive this optimization by checking that count (like we
used to) instead of the total free objects count.
Change-Id: I43658707a1c61674d0366124d5976b00d98741a9
Reviewed-on: https://go-review.googlesource.com/22596
Run-TryBot: Austin Clements <austin@google.com>
Reviewed-by: Rick Hudson <rlh@golang.org>
Commit 8dda1c4 changed the meaning of "nfree" in sweep from the number
of newly freed objects to the total number of free objects in the
span, but didn't update where sweep added nfree to c.local_nsmallfree.
Hence, we're over-accounting the number of frees. This is causing
TestArrayHash to fail with "too many allocs NNN - hash not balanced".
Fix this by computing the number of newly freed objects and adding
that to c.local_nsmallfree, so it behaves like it used to. Computing
this requires a small tweak to mallocgc: apparently we've never set
s.allocCount when allocating a large object; fix this by setting it to
1 so sweep doesn't get confused.
Change-Id: I31902ffd310110da4ffd807c5c06f1117b872dc8
Reviewed-on: https://go-review.googlesource.com/22595
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
We broke tracing of freed objects in GODEBUG=allocfreetrace=1 mode
when we removed the sweep over the mark bitmap. Fix it by
re-introducing the sweep over the bitmap specifically if we're in
allocfreetrace mode. This doesn't have to be even remotely efficient,
since the overhead of allocfreetrace is huge anyway, so we can keep
the code for this down to just a few lines.
Change-Id: I9e176b3b04c73608a0ea3068d5d0cd30760ebd40
Reviewed-on: https://go-review.googlesource.com/22592
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Rick Hudson <rlh@golang.org>
Currently we always zero objects when we allocate them. We used to
have an optimization that would not zero objects that had not been
allocated since the whole span was last zeroed (either by getting it
from the system or by getting it from the heap, which does a bulk
zero), but this depended on the sweeper clobbering the first two words
of each object. Hence, we lost this optimization when the bitmap
sweeper went away.
Re-introduce this optimization using a different mechanism. Each span
already keeps a flag indicating that it just came from the OS or was
just bulk zeroed by the mheap. We can simply use this flag to know
when we don't need to zero an object. This is slightly less efficient
than the old optimization: if a span gets allocated and partially
used, then GC happens and the span gets returned to the mcentral, then
the span gets re-acquired, the old optimization knew that it only had
to re-zero the objects that had been reclaimed, whereas this
optimization will re-zero everything. However, in this case, you're
already paying for the garbage collection, and you've only wasted one
zeroing of the span, so in practice there seems to be little
difference. (If we did want to revive the full optimization, each span
could keep track of a frontier beyond which all free slots are zeroed.
I prototyped this and it didn't obvious do any better than the much
simpler approach in this commit.)
This significantly improves BinaryTree17, which is allocation-heavy
(and runs first, so most pages are already zeroed), and slightly
improves everything else.
name old time/op new time/op delta
XBenchGarbage-12 2.15ms ± 1% 2.14ms ± 1% -0.80% (p=0.000 n=17+17)
name old time/op new time/op delta
BinaryTree17-12 2.71s ± 1% 2.56s ± 1% -5.73% (p=0.000 n=18+19)
DivconstI64-12 1.70ns ± 1% 1.70ns ± 1% ~ (p=0.562 n=18+18)
DivconstU64-12 1.74ns ± 2% 1.74ns ± 1% ~ (p=0.394 n=20+20)
DivconstI32-12 1.74ns ± 0% 1.74ns ± 0% ~ (all samples are equal)
DivconstU32-12 1.66ns ± 1% 1.66ns ± 0% ~ (p=0.516 n=15+16)
DivconstI16-12 1.84ns ± 0% 1.84ns ± 0% ~ (all samples are equal)
DivconstU16-12 1.82ns ± 0% 1.82ns ± 0% ~ (all samples are equal)
DivconstI8-12 1.79ns ± 0% 1.79ns ± 0% ~ (all samples are equal)
DivconstU8-12 1.60ns ± 0% 1.60ns ± 1% ~ (p=0.603 n=17+19)
Fannkuch11-12 2.11s ± 1% 2.11s ± 0% ~ (p=0.333 n=16+19)
FmtFprintfEmpty-12 45.1ns ± 4% 45.4ns ± 5% ~ (p=0.111 n=20+20)
FmtFprintfString-12 134ns ± 0% 129ns ± 0% -3.45% (p=0.000 n=18+16)
FmtFprintfInt-12 131ns ± 1% 129ns ± 1% -1.54% (p=0.000 n=16+18)
FmtFprintfIntInt-12 205ns ± 2% 203ns ± 0% -0.56% (p=0.014 n=20+18)
FmtFprintfPrefixedInt-12 200ns ± 2% 197ns ± 1% -1.48% (p=0.000 n=20+18)
FmtFprintfFloat-12 256ns ± 1% 256ns ± 0% -0.21% (p=0.008 n=18+20)
FmtManyArgs-12 805ns ± 0% 804ns ± 0% -0.19% (p=0.001 n=18+18)
GobDecode-12 7.21ms ± 1% 7.14ms ± 1% -0.92% (p=0.000 n=19+20)
GobEncode-12 5.88ms ± 1% 5.88ms ± 1% ~ (p=0.641 n=18+19)
Gzip-12 218ms ± 1% 218ms ± 1% ~ (p=0.271 n=19+18)
Gunzip-12 37.1ms ± 0% 36.9ms ± 0% -0.29% (p=0.000 n=18+17)
HTTPClientServer-12 78.1µs ± 2% 77.4µs ± 2% ~ (p=0.070 n=19+19)
JSONEncode-12 15.5ms ± 1% 15.5ms ± 0% ~ (p=0.063 n=20+18)
JSONDecode-12 56.1ms ± 0% 55.4ms ± 1% -1.18% (p=0.000 n=19+18)
Mandelbrot200-12 4.05ms ± 0% 4.06ms ± 0% +0.29% (p=0.001 n=18+18)
GoParse-12 3.28ms ± 1% 3.21ms ± 1% -2.30% (p=0.000 n=20+20)
RegexpMatchEasy0_32-12 69.4ns ± 2% 69.3ns ± 1% ~ (p=0.205 n=18+16)
RegexpMatchEasy0_1K-12 239ns ± 0% 239ns ± 0% ~ (all samples are equal)
RegexpMatchEasy1_32-12 69.4ns ± 1% 69.4ns ± 1% ~ (p=0.620 n=15+18)
RegexpMatchEasy1_1K-12 370ns ± 1% 369ns ± 2% ~ (p=0.088 n=20+20)
RegexpMatchMedium_32-12 108ns ± 0% 108ns ± 0% ~ (all samples are equal)
RegexpMatchMedium_1K-12 33.6µs ± 3% 33.5µs ± 3% ~ (p=0.718 n=20+20)
RegexpMatchHard_32-12 1.68µs ± 1% 1.67µs ± 2% ~ (p=0.316 n=20+20)
RegexpMatchHard_1K-12 50.5µs ± 3% 50.4µs ± 3% ~ (p=0.659 n=20+20)
Revcomp-12 381ms ± 1% 381ms ± 1% ~ (p=0.916 n=19+18)
Template-12 66.5ms ± 1% 65.8ms ± 2% -1.08% (p=0.000 n=20+20)
TimeParse-12 317ns ± 0% 319ns ± 0% +0.48% (p=0.000 n=19+12)
TimeFormat-12 338ns ± 0% 338ns ± 0% ~ (p=0.124 n=19+18)
[Geo mean] 5.99µs 5.96µs -0.54%
Change-Id: I638ffd9d9f178835bbfa499bac20bd7224f1a907
Reviewed-on: https://go-review.googlesource.com/22591
Reviewed-by: Rick Hudson <rlh@golang.org>
This makes compress/flate's version of Snappy diverge from the upstream
golang/snappy version, but the latter has a goal of matching C++ snappy
output byte-for-byte. Both C++ and the asm version of golang/snappy can
use a smaller N for the O(N) zero-initialization of the hash table when
the input is small, even if the pure Go golang/snappy algorithm cannot:
"var table [tableSize]uint16" zeroes all tableSize elements.
For this package, we don't have the match-C++-snappy goal, so we can use
a different (constant) hash table size.
This is a small win, in terms of throughput and output size, but it also
enables us to re-use the (constant size) hash table between
encodeBestSpeed calls, avoiding the cost of zero-initializing the hash
table altogether. This will be implemented in follow-up commits.
This package's benchmarks:
name old speed new speed delta
EncodeDigitsSpeed1e4-8 72.8MB/s ± 1% 73.5MB/s ± 1% +0.86% (p=0.000 n=10+10)
EncodeDigitsSpeed1e5-8 77.5MB/s ± 1% 78.0MB/s ± 0% +0.69% (p=0.000 n=10+10)
EncodeDigitsSpeed1e6-8 82.0MB/s ± 1% 82.7MB/s ± 1% +0.85% (p=0.000 n=10+9)
EncodeTwainSpeed1e4-8 65.1MB/s ± 1% 65.6MB/s ± 0% +0.78% (p=0.000 n=10+9)
EncodeTwainSpeed1e5-8 80.0MB/s ± 0% 80.6MB/s ± 1% +0.66% (p=0.000 n=9+10)
EncodeTwainSpeed1e6-8 81.6MB/s ± 1% 82.1MB/s ± 1% +0.55% (p=0.017 n=10+10)
Input size in bytes, output size (and time taken) before and after on
some larger files:
1073741824 57269781 ( 3183ms) 57269781 ( 3177ms) adresser.001
1000000000 391052000 ( 11071ms) 391051996 ( 11067ms) enwik9
1911399616 378679516 ( 13450ms) 378679514 ( 13079ms) gob-stream
8558382592 3972329193 ( 99962ms) 3972329193 ( 91290ms) rawstudio-mint14.tar
200000000 200015265 ( 776ms) 200015265 ( 774ms) sharnd.out
Thanks to Klaus Post for the original suggestion on cl/21021.
Change-Id: Ia4c63a8d1b92c67e1765ec5c3c8c69d289d9a6ce
Reviewed-on: https://go-review.googlesource.com/22604
Reviewed-by: Russ Cox <rsc@golang.org>
Drive by gardening of bv.go.
- Unexport the Bvec type, it is not used outside internal/gc.
(machine translated with gofmt -r)
- Removed unused constants and functions.
(driven by cmd/unused)
Change-Id: I3433758ad4e62439f802f4b0ed306e67336d9aba
Reviewed-on: https://go-review.googlesource.com/22602
Run-TryBot: Dave Cheney <dave@cheney.net>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
After CL 22461, c-archive build on darwin/arm is by default compiled
with -shared and installed in pkg/darwin_arm_shared.
Fix build (2nd time...)
Change-Id: Ia2bb09bb6e1ebc9bc74f7570dd80c81d05eaf744
Reviewed-on: https://go-review.googlesource.com/22534
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This encoding algorithm, which prioritizes speed over output size, is
based on Snappy's LZ77-style encoder: github.com/golang/snappy
This commit keeps the diff between this package's encodeBestSpeed
function and and Snappy's encodeBlock function as small as possible (see
the diff below). Follow-up commits will improve this package's
performance and output size.
This package's speed benchmarks:
name old speed new speed delta
EncodeDigitsSpeed1e4-8 40.7MB/s ± 0% 73.0MB/s ± 0% +79.18% (p=0.008 n=5+5)
EncodeDigitsSpeed1e5-8 33.0MB/s ± 0% 77.3MB/s ± 1% +134.04% (p=0.008 n=5+5)
EncodeDigitsSpeed1e6-8 32.1MB/s ± 0% 82.1MB/s ± 0% +156.18% (p=0.008 n=5+5)
EncodeTwainSpeed1e4-8 42.1MB/s ± 0% 65.0MB/s ± 0% +54.61% (p=0.008 n=5+5)
EncodeTwainSpeed1e5-8 46.3MB/s ± 0% 80.0MB/s ± 0% +72.81% (p=0.008 n=5+5)
EncodeTwainSpeed1e6-8 47.3MB/s ± 0% 81.7MB/s ± 0% +72.86% (p=0.008 n=5+5)
Here's the milliseconds taken, before and after this commit, to compress
a number of test files:
Go's src/compress/testdata files:
4 1 e.txt
8 4 Mark.Twain-Tom.Sawyer.txt
github.com/golang/snappy's benchmark files:
3 1 alice29.txt
12 3 asyoulik.txt
6 1 fireworks.jpeg
1 1 geo.protodata
1 0 html
2 2 html_x_4
6 3 kppkn.gtb
11 4 lcet10.txt
5 1 paper-100k.pdf
14 6 plrabn12.txt
17 6 urls.10K
Larger files linked to from
https://docs.google.com/spreadsheets/d/1VLxi-ac0BAtf735HyH3c1xRulbkYYUkFecKdLPH7NIQ/edit#gid=166102500
2409 3182 adresser.001
16757 11027 enwik9
13764 12946 gob-stream
153978 74317 rawstudio-mint14.tar
4371 770 sharnd.out
Output size is larger. In the table below, the first column is the input
size, the second column is the output size prior to this commit, the
third column is the output size after this commit.
100003 47707 50006 e.txt
387851 172707 182930 Mark.Twain-Tom.Sawyer.txt
152089 62457 66705 alice29.txt
125179 54503 57274 asyoulik.txt
123093 122827 123108 fireworks.jpeg
118588 18574 20558 geo.protodata
102400 16601 17305 html
409600 65506 70313 html_x_4
184320 49007 50944 kppkn.gtb
426754 166957 179355 lcet10.txt
102400 82126 84937 paper-100k.pdf
481861 218617 231988 plrabn12.txt
702087 241774 258020 urls.10K
1073741824 43074110 57269781 adresser.001
1000000000 365772256 391052000 enwik9
1911399616 340364558 378679516 gob-stream
8558382592 3807229562 3972329193 rawstudio-mint14.tar
200000000 200061040 200015265 sharnd.out
The diff between github.com/golang/snappy's encodeBlock function and
this commit's encodeBestSpeed function:
1c1,7
< func encodeBlock(dst, src []byte) (d int) {
---
> func encodeBestSpeed(dst []token, src []byte) []token {
> // This check isn't in the Snappy implementation, but there, the caller
> // instead of the callee handles this case.
> if len(src) < minNonLiteralBlockSize {
> return emitLiteral(dst, src)
> }
>
4c10
< // and len(src) <= maxBlockSize and maxBlockSize == 65536.
---
> // and len(src) <= maxStoreBlockSize and maxStoreBlockSize == 65535.
65c71
< if load32(src, s) == load32(src, candidate) {
---
> if s-candidate < maxOffset && load32(src, s) == load32(src, candidate) {
73c79
< d += emitLiteral(dst[d:], src[nextEmit:s])
---
> dst = emitLiteral(dst, src[nextEmit:s])
90c96
< // This is an inlined version of:
---
> // This is an inlined version of Snappy's:
93c99,103
< for i := candidate + 4; s < len(src) && src[i] == src[s]; i, s = i+1, s+1 {
---
> s1 := base + maxMatchLength
> if s1 > len(src) {
> s1 = len(src)
> }
> for i := candidate + 4; s < s1 && src[i] == src[s]; i, s = i+1, s+1 {
96c106,107
< d += emitCopy(dst[d:], base-candidate, s-base)
---
> // matchToken is flate's equivalent of Snappy's emitCopy.
> dst = append(dst, matchToken(uint32(s-base-3), uint32(base-candidate-minOffsetSize)))
114c125
< if uint32(x>>8) != load32(src, candidate) {
---
> if s-candidate >= maxOffset || uint32(x>>8) != load32(src, candidate) {
124c135
< d += emitLiteral(dst[d:], src[nextEmit:])
---
> dst = emitLiteral(dst, src[nextEmit:])
126c137
< return d
---
> return dst
This change is based on https://go-review.googlesource.com/#/c/21021/ by
Klaus Post, but it is a separate changelist as cl/21021 seems to have
stalled in code review, and the Go 1.7 feature freeze approaches.
Golang-dev discussion:
https://groups.google.com/d/topic/golang-dev/XYgHX9p8IOk/discussion and
of course cl/21021.
Change-Id: Ib662439417b3bd0b61c2977c12c658db3e44d164
Reviewed-on: https://go-review.googlesource.com/22370
Reviewed-by: Russ Cox <rsc@golang.org>
This converts all remaining uses of mspan.start to instead use
mspan.base(). In many cases, this actually reduces the complexity of
the code.
Change-Id: If113840e00d3345a6cf979637f6a152e6344aee7
Reviewed-on: https://go-review.googlesource.com/22590
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
Currently we have lots of (s.start << _PageShift) and variants. We now
have an s.base() function that returns this. It's faster and more
readable, so use it.
Change-Id: I888060a9dae15ea75ca8cc1c2b31c905e71b452b
Reviewed-on: https://go-review.googlesource.com/22559
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
These used to be used for the list of newly freed objects, but that's
no longer a thing.
Change-Id: I5a4503137b74ec0eae5372ca271b1aa0b32df074
Reviewed-on: https://go-review.googlesource.com/22557
Reviewed-by: Rick Hudson <rlh@golang.org>
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
.bss section has no data stored in PE file. But when .bss section data
is used by the linker it is assumed that its every byte is set to zero.
(*Section).Data returns garbage at this moment. Change (*Section).Data
so it returns slice filled with 0s.
Updates #15345
Change-Id: I1fa5138244a9447e1d59dec24178b1dd0fd4c5d7
Reviewed-on: https://go-review.googlesource.com/22544
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Alex Brainman <alex.brainman@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
This is an error according to the spec, but Firefox and Google Chrome
seem OK with this.
Fixes#15059.
Change-Id: I841cf44e96655e91a2481555f38fbd7055a32202
Reviewed-on: https://go-review.googlesource.com/22546
Reviewed-by: Rob Pike <r@golang.org>
Our compilers now provides instrinsics including
sys.Ctz64 that support CTZ (count trailing zero)
instructions. This CL replaces the Go versions
of CTZ with the compiler intrinsic.
Count trailing zeros CTZ finds the least
significant 1 in a word and returns the number
of less significant 0s in the word.
Allocation uses the bitmap created by the garbage
collector to locate an unmarked object. The logic
takes a word of the bitmap, complements, and then
caches it. It then uses CTZ to locate an available
unmarked object. It then shifts marked bits out of
the bitmap word preparing it for the next search.
Once all the unmarked objects are used in the
cached work the bitmap gets another word and
repeats the process.
Change-Id: Id2fc42d1d4b9893efaa2e1bd01896985b7e42f82
Reviewed-on: https://go-review.googlesource.com/21366
Reviewed-by: Austin Clements <austin@google.com>
Two changes are included here that are dependent on the other.
The first is that allocBits and gcamrkBits are changed to
a *uint8 which points to the first byte of that span's
mark and alloc bits. Several places were altered to
perform pointer arithmetic to locate the byte corresponding
to an object in the span. The actual bit corresponding
to an object is indexed in the byte by using the lower three
bits of the objects index.
The second change avoids the redundant calculation of an
object's index. The index is returned from heapBitsForObject
and then used by the functions indexing allocBits
and gcmarkBits.
Finally we no longer allocate the gc bits in the span
structures. Instead we use an arena based allocation scheme
that allows for a more compact bit map as well as recycling
and bulk clearing of the mark bits.
Change-Id: If4d04b2021c092ec39a4caef5937a8182c64dfef
Reviewed-on: https://go-review.googlesource.com/20705
Reviewed-by: Austin Clements <austin@google.com>
golang.org/cl/22453 was supposed to pass -no-pie to the linker when linking a
race-enabled binary if the host toolchain supports it. But I bungled the
supported check as I forgot to pass -c to the host compiler so it tried to
compile a 0 byte .c file into an executable, which will never work. Fix it to
pass -c as it should have all along.
Change-Id: I4801345c7a29cb18d5f22cec5337ce535f92135d
Reviewed-on: https://go-review.googlesource.com/22587
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>
