Re: [PATCH] makedumpfile: Improve progress information for huge memory system.

Backport from upstream. commit 20ecc0827e7837c52f3903638a59959f8bf17f9e Author: HATAYAMA Daisuke <d.hatayama(a)jp.fujitsu.com&gt; Date: Tue Nov 5 00:29:35 2013 +0900 [PATCH v2] Improve progress information for huge memory system. On system with huge memory, percentage in progress information is updated at very slow interval, because 1 percent on 1 TiB memory is about 10 GiB, which looks like as if system has freezed. Then, confused users might get tempted to push a reset button to recover the system. We want to avoid such situation as much as possible. Signed-off-by: HATAYAMA Daisuke <d.hatayama(a)jp.fujitsu.com&gt; Signed-off-by: Baoquan He <bhe(a)redhat.com&gt;

--- ...prove-progress-information-for-huge-memor.patch | 200 +++++++++++++++++++++ 1 file changed, 200 insertions(+) create mode 100644 kexec-tools-2.0.4-makedumpfile-Improve-progress-information-for-huge-memor.patch diff --git a/kexec-tools-2.0.4-makedumpfile-Improve-progress-information-for-huge-memor.patch b/kexec-tools-2.0.4-makedumpfile-Improve-progress-information-for-huge-memor.patch new file mode 100644 index 0000000..9b15185 --- /dev/null +++ b/kexec-tools-2.0.4-makedumpfile-Improve-progress-information-for-huge-memor.patch @@ -0,0 +1,200 @@ +From 20ecc0827e7837c52f3903638a59959f8bf17f9e Mon Sep 17 00:00:00 2001 +From: HATAYAMA Daisuke <d.hatayama(a)jp.fujitsu.com&gt; +Date: Tue, 5 Nov 2013 00:29:35 +0900 +Subject: [PATCH] [PATCH v2] Improve progress information for huge memory + system. + +On system with huge memory, percentage in progress information is +updated at very slow interval, because 1 percent on 1 TiB memory is +about 10 GiB, which looks like as if system has freezed. Then, +confused users might get tempted to push a reset button to recover the +system. We want to avoid such situation as much as possible. + +To address the issue, this patch: + +- increases the number of calling print_progress() from once in + (written pages / 100)-pages to once in (written pages / + 10000)-pages, + +- extends precision in progress information by adding 1 digit to its + fractional part, and + +- adds spinner that rotates in the order of /, |, \ and - in next to + the progress indicator in percentage, + +which help users to get aware that system is still active and crash +dump process is still in progress now. + +The spinner code is borrowed from diskdump code. + +The ouput is changed from: + +Copying data : [ 0 %] / +Copying data : [ 8 %] | +Copying data : [ 11 %] \ +Copying data : [ 14 %] - +Copying data : [ 16 %] / +... +Copying data : [ 99 %] / +Copying data : [100 %] | + +to: + +Copying data : [ 0.1 %] / +Copying data : [ 8.9 %] | +Copying data : [ 11.6 %] \ +Copying data : [ 14.3 %] - +Copying data : [ 16.4 %] / +... +Copying data : [ 99.2 %] / +Copying data : [100.0 %] | + +This patch doesn't adopt purely time-based approach that records the +time when print_progress() is called at each invocation and print the +recorded time if it is strictly larger than the previous time value. + +The problem is that calling time() system call amounts to +considertably long time in total on huge memory system. For example, +here is a simple bench that measures total execution time of time() +system call for (1TiB / 4KiB)-times: + +$ ./bench +total: 18.360503 +total: 34.910297 + +the result of which reveals that it amounts to about 20 seconds with +vDSO optimization and about 35 seconds without. + +BTW, on our 12 TiB memory system, we collect about 300 GiB crash dump +in about 40 minutes with dump level 31. On 12TiB, the benchmark result +corresponds to about 4 minutes and 7 minutes respectively, both of which +affects a whole performance. + +==bench.c +static inline double getdtime(void) +{ + struct timeval tv; + gettimeofday(&tv, NULL); + return (double)tv.tv_sec + (double)tv.tv_usec * 1.0e-6; +} + +int main(int argc, char **argv) +{ + unsigned long i; + time_t t; + double t1, t2, total; + const int NR_time = 201; + const unsigned long nr_repeat = (1UL << 40) / 4096; + + total = 0; + for (i = 0; i < nr_repeat; ++i) { + t1 = getdtime(); + time(&t); + t2 = getdtime(); + total += t2 - t1; + } + printf("total: %lf\n", total); + + total = 0; + for (i = 0; i < nr_repeat; ++i) { + t1 = getdtime(); + syscall(NR_time, &t); + t2 = getdtime(); + total += t2 - t1; + } + printf("total: %lf\n", total); + + return 0; +} +== + +Signed-off-by: HATAYAMA Daisuke <d.hatayama(a)jp.fujitsu.com&gt; +--- + makedumpfile.c | 8 ++++---- + print_info.c | 15 +++++++++------ + 2 files changed, 13 insertions(+), 10 deletions(-) + +diff --git a/makedumpfile-1.5.4/makedumpfile.c b/makedumpfile-1.5.4/makedumpfile.c +index dafe83b..3746cf6 100644 +--- a/makedumpfile-1.5.4/makedumpfile.c ++++ b/makedumpfile-1.5.4/makedumpfile.c +@@ -5573,7 +5573,7 @@ write_elf_pages(struct cache_data *cd_header, struct cache_data *cd_page) + initialize_2nd_bitmap(&bitmap2); + + num_dumpable = get_num_dumpable(); +- per = num_dumpable / 100; ++ per = num_dumpable / 10000; + + off_seg_load = info->offset_load_dumpfile; + cd_page->offset = info->offset_load_dumpfile; +@@ -5858,7 +5858,7 @@ write_elf_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_page) + return FALSE; + + num_dumpable = info->num_dumpable; +- per = num_dumpable / 100; ++ per = num_dumpable / 10000; + + off_seg_load = info->offset_load_dumpfile; + cd_page->offset = info->offset_load_dumpfile; +@@ -6116,7 +6116,7 @@ write_kdump_pages(struct cache_data *cd_header, struct cache_data *cd_page) + } + + num_dumpable = get_num_dumpable(); +- per = num_dumpable / 100; ++ per = num_dumpable / 10000; + + /* + * Calculate the offset of the page data. +@@ -6317,7 +6317,7 @@ write_kdump_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_pag + goto out; + } + +- per = info->num_dumpable / 100; ++ per = info->num_dumpable / 10000; + + /* + * Set a fileoffset of Physical Address 0x0. +diff --git a/makedumpfile-1.5.4/print_info.c b/makedumpfile-1.5.4/print_info.c +index 3527970..d7a8600 100644 +--- a/makedumpfile-1.5.4/print_info.c ++++ b/makedumpfile-1.5.4/print_info.c +@@ -283,27 +283,30 @@ print_usage(void) + void + print_progress(const char *msg, unsigned long current, unsigned long end) + { +- int progress; ++ float progress; + time_t tm; + static time_t last_time = 0; ++ static unsigned int lapse = 0; ++ static const char *spinner = "/|\\-"; + + if (current < end) { + tm = time(NULL); + if (tm - last_time < 1) + return; + last_time = tm; +- progress = current * 100 / end; ++ progress = (float)current * 100 / end; + } else + progress = 100; + + if (flag_ignore_r_char) { +- PROGRESS_MSG("%-" PROGRESS_MAXLEN "s: [%3d %%]\n", +- msg, progress); ++ PROGRESS_MSG("%-" PROGRESS_MAXLEN "s: [%5.1f %%] %c\n", ++ msg, progress, spinner[lapse % 4]); + } else { + PROGRESS_MSG("\r"); +- PROGRESS_MSG("%-" PROGRESS_MAXLEN "s: [%3d %%] ", +- msg, progress); ++ PROGRESS_MSG("%-" PROGRESS_MAXLEN "s: [%5.1f %%] %c", ++ msg, progress, spinner[lapse % 4]); + } ++ lapse++; + } + + void +-- +1.8.3.1 + -- 1.8.3.1