From: Richard Henderson <rth@twiddle.net>
To: qemu-devel@nongnu.org
Cc: peter.maydell@linaro.org, "Emilio G. Cota" <cota@braap.org>
Subject: [Qemu-devel] [PULL 15/15] translate-all: add tb hash bucket info to 'info jit' dump
Date: Fri, 10 Jun 2016 07:26:53 -0700 [thread overview]
Message-ID: <1465568813-19771-16-git-send-email-rth@twiddle.net> (raw)
In-Reply-To: <1465568813-19771-1-git-send-email-rth@twiddle.net>
From: "Emilio G. Cota" <cota@braap.org>
Examples:
- Good hashing, i.e. tb_hash_func5(phys_pc, pc, flags):
TB count 715135/2684354
[...]
TB hash buckets 388775/524288 (74.15% head buckets used)
TB hash occupancy 33.04% avg chain occ. Histogram: [0,10)%|▆ █ ▅▁▃▁▁|[90,100]%
TB hash avg chain 1.017 buckets. Histogram: 1|█▁▁|3
- Not-so-good hashing, i.e. tb_hash_func5(phys_pc, pc, 0):
TB count 712636/2684354
[...]
TB hash buckets 344924/524288 (65.79% head buckets used)
TB hash occupancy 31.64% avg chain occ. Histogram: [0,10)%|█ ▆ ▅▁▃▁▂|[90,100]%
TB hash avg chain 1.047 buckets. Histogram: 1|█▁▁▁|4
- Bad hashing, i.e. tb_hash_func5(phys_pc, 0, 0):
TB count 702818/2684354
[...]
TB hash buckets 112741/524288 (21.50% head buckets used)
TB hash occupancy 10.15% avg chain occ. Histogram: [0,10)%|█ ▁ ▁▁▁▁▁|[90,100]%
TB hash avg chain 2.107 buckets. Histogram: [1.0,10.2)|█▁▁▁▁▁▁▁▁▁|[83.8,93.0]
- Good hashing, but no auto-resize:
TB count 715634/2684354
TB hash buckets 8192/8192 (100.00% head buckets used)
TB hash occupancy 98.30% avg chain occ. Histogram: [95.3,95.8)%|▁▁▃▄▃▄▁▇▁█|[99.5,100.0]%
TB hash avg chain 22.070 buckets. Histogram: [15.0,16.7)|▁▂▅▄█▅▁▁▁▁|[30.3,32.0]
Acked-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Suggested-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1465412133-3029-16-git-send-email-cota@braap.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
---
translate-all.c | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/translate-all.c b/translate-all.c
index b620fcc..e8b88b4 100644
--- a/translate-all.c
+++ b/translate-all.c
@@ -1668,6 +1668,10 @@ void dump_exec_info(FILE *f, fprintf_function cpu_fprintf)
int i, target_code_size, max_target_code_size;
int direct_jmp_count, direct_jmp2_count, cross_page;
TranslationBlock *tb;
+ struct qht_stats hst;
+ uint32_t hgram_opts;
+ size_t hgram_bins;
+ char *hgram;
target_code_size = 0;
max_target_code_size = 0;
@@ -1718,6 +1722,38 @@ void dump_exec_info(FILE *f, fprintf_function cpu_fprintf)
direct_jmp2_count,
tcg_ctx.tb_ctx.nb_tbs ? (direct_jmp2_count * 100) /
tcg_ctx.tb_ctx.nb_tbs : 0);
+
+ qht_statistics_init(&tcg_ctx.tb_ctx.htable, &hst);
+
+ cpu_fprintf(f, "TB hash buckets %zu/%zu (%0.2f%% head buckets used)\n",
+ hst.used_head_buckets, hst.head_buckets,
+ (double)hst.used_head_buckets / hst.head_buckets * 100);
+
+ hgram_opts = QDIST_PR_BORDER | QDIST_PR_LABELS;
+ hgram_opts |= QDIST_PR_100X | QDIST_PR_PERCENT;
+ if (qdist_xmax(&hst.occupancy) - qdist_xmin(&hst.occupancy) == 1) {
+ hgram_opts |= QDIST_PR_NODECIMAL;
+ }
+ hgram = qdist_pr(&hst.occupancy, 10, hgram_opts);
+ cpu_fprintf(f, "TB hash occupancy %0.2f%% avg chain occ. Histogram: %s\n",
+ qdist_avg(&hst.occupancy) * 100, hgram);
+ g_free(hgram);
+
+ hgram_opts = QDIST_PR_BORDER | QDIST_PR_LABELS;
+ hgram_bins = qdist_xmax(&hst.chain) - qdist_xmin(&hst.chain);
+ if (hgram_bins > 10) {
+ hgram_bins = 10;
+ } else {
+ hgram_bins = 0;
+ hgram_opts |= QDIST_PR_NODECIMAL | QDIST_PR_NOBINRANGE;
+ }
+ hgram = qdist_pr(&hst.chain, hgram_bins, hgram_opts);
+ cpu_fprintf(f, "TB hash avg chain %0.3f buckets. Histogram: %s\n",
+ qdist_avg(&hst.chain), hgram);
+ g_free(hgram);
+
+ qht_statistics_destroy(&hst);
+
cpu_fprintf(f, "\nStatistics:\n");
cpu_fprintf(f, "TB flush count %d\n", tcg_ctx.tb_ctx.tb_flush_count);
cpu_fprintf(f, "TB invalidate count %d\n",
--
2.5.5
next prev parent reply other threads:[~2016-06-10 14:27 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-10 14:26 [Qemu-devel] [PULL 00/15] tb hash improvements Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 01/15] compiler.h: add QEMU_ALIGNED() to enforce struct alignment Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 02/15] seqlock: remove optional mutex Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 03/15] seqlock: rename write_lock/unlock to write_begin/end Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 04/15] include/processor.h: define cpu_relax() Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 05/15] qemu-thread: add simple test-and-set spinlock Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 06/15] exec: add tb_hash_func5, derived from xxhash Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 07/15] tb hash: hash phys_pc, pc, and flags with xxhash Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 08/15] qdist: add module to represent frequency distributions of data Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 09/15] qdist: add test program Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 10/15] qht: QEMU's fast, resizable and scalable Hash Table Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 11/15] qht: add test program Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 12/15] qht: add qht-bench, a performance benchmark Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 13/15] qht: add test-qht-par to invoke qht-bench from 'check' target Richard Henderson
2016-06-10 14:26 ` [Qemu-devel] [PULL 14/15] tb hash: track translated blocks with qht Richard Henderson
2016-08-10 13:36 ` Igor Mammedov
2016-08-10 19:25 ` [Qemu-devel] [PATCH] qht: support resetting an uninitialized qht Emilio G. Cota
2016-08-11 8:43 ` Igor Mammedov
2016-06-10 14:26 ` Richard Henderson [this message]
2016-07-22 9:04 ` [Qemu-devel] [PULL 15/15] translate-all: add tb hash bucket info to 'info jit' dump Changlong Xie
2016-07-22 16:36 ` [Qemu-devel] [PATCH] qht: do not segfault when gathering stats from an uninitialized qht Emilio G. Cota
2016-07-23 7:45 ` Paolo Bonzini
2016-07-23 10:01 ` Peter Maydell
2016-07-23 10:54 ` Paolo Bonzini
2016-07-23 23:09 ` Emilio G. Cota
2016-06-10 15:33 ` [Qemu-devel] [PULL 00/15] tb hash improvements Peter Maydell
2016-06-10 15:57 ` Peter Maydell
2016-06-10 16:34 ` Emilio G. Cota
2016-06-10 16:41 ` Peter Maydell
2016-06-10 19:24 ` Emilio G. Cota
2016-06-11 23:09 ` Richard Henderson
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1465568813-19771-16-git-send-email-rth@twiddle.net \
--to=rth@twiddle.net \
--cc=cota@braap.org \
--cc=peter.maydell@linaro.org \
--cc=qemu-devel@nongnu.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.