>Recently people complained that they don't know how to decide how
>much disk size need be reserved for kdump. E.g there are lots of
>machines with different memory size, if the memory usage information
>of current system can be shown, that can help them to make an estimate
>how much storage space need be reserved.
>
>In this patch, a new interface is added into makedumpfile. By the
>help of this, people can know the page number of memory in different
>use. The implementation is analyzing the "System Ram" and "kernel text"
>program segment of /proc/kcore excluding the crashkernel range, then
>calculating the page number of different kind per vmcoreinfo.
>
>The print is like below:
>->$ ./makedumpfile --mem-usage /proc/kcore
>Excluding unnecessary pages : [100.0 %] |
>
>Page number of memory in different use
>--------------------------------------------------
>TYPE PAGES EXCLUDABLE DESCRIPTION
>ZERO 0 yes Pages filled with zero
The number of zero pages is always 0 since it isn't counted during
get_num_dumpable_cyclic(). To count it up, we have to read all of the
pages like exclude_zero_pages(), so we need "exclude_zero_pages_cyclic()".
My idea is to call it in get_num_dumpable_cyclic() like:
for_each_cycle(0, info->max_mapnr, &cycle)
{
if (!exclude_unnecessary_pages_cyclic(&cycle))
return FALSE;
+ if (info->flag_mem_usage)
+ exclude_zero_pages_cyclic(&cycle);
+
for(pfn=cycle.start_pfn; pfn<cycle.end_pfn; pfn++)
BTW, what is the target kernel version of this feature?
It works well on 3.12 but fails on 2.6.32 like:
# ./makedumpfile --mem-usage /proc/kcore
read_device: Can't read a file(/proc/kcore). Success
set_kcore_vmcoreinfo: Can't read the dump memory(/proc/kcore). Success
makedumpfile Failed.
#
This error means reading VMCOREINFO from /proc/kcore was failed.
Of course, there is a VMCOREINFO on the memory,
# cat /sys/kernel/vmcoreinfo
1e01b80 1000
#
It seems like old /proc/kcore's issue, but I'm still investigating.
Any comments are helpful.
Thanks
Atsushi Kumagai
>CACHE 562006 yes Cache pages
>CACHE_PRIVATE 353502 yes Cache pages + private
>USER 225780 yes User process pages
>FREE 2761884 yes Free pages
>KERN_DATA 235873 no Dumpable kernel data
>
>Total pages on system: 4139045
>
>Signed-off-by: Baoquan He <bhe at redhat.com>
>---
> makedumpfile.8 | 17 +++++++++++++
> makedumpfile.c | 76 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> makedumpfile.h | 2 ++
> print_info.c | 8 +++++++
> 4 files changed, 103 insertions(+)
>
>diff --git a/makedumpfile.8 b/makedumpfile.8
>index 25fe74e..64abbc7 100644
>--- a/makedumpfile.8
>+++ b/makedumpfile.8
>@@ -532,6 +532,23 @@ it is necessary to specfiy [\-x \fIVMLINUX\fR] or [\-i \fIVMCOREINFO\fR].
> # makedumpfile \-\-dump-dmesg -x vmlinux /proc/vmcore dmesgfile
> .br
>
>+
>+.TP
>+\fB\-\-mem-usage\fR
>+This option is used to show the page numbers of current system in different
>+use. It should be executed in 1st kernel. By the help of this, user can know
>+how many pages is dumpable when different dump_level is specified. It analyzes
>+the 'System Ram' and 'kernel text' program segment of /proc/kcore excluding
>+the crashkernel range, then calculates the page number of different kind per
>+vmcoreinfo. So currently /proc/kcore need be specified explicitly.
>+
>+.br
>+.B Example:
>+.br
>+# makedumpfile \-\-mem-usage /proc/kcore
>+.br
>+
>+
> .TP
> \fB\-\-diskset=VMCORE\fR
> Specify multiple \fIVMCORE\fRs created on sadump diskset configuration
>diff --git a/makedumpfile.c b/makedumpfile.c
>index b5e920d..6bbf324 100644
>--- a/makedumpfile.c
>+++ b/makedumpfile.c
>@@ -7853,6 +7853,7 @@ print_mem_usage(void)
> shrinking = shrinking / pfn_original;
>
> MSG("\n");
>+ MSG("\n");
> MSG("Page number of memory in different use\n");
> MSG("--------------------------------------------------\n");
> MSG("TYPE PAGES EXCLUDABLE DESCRIPTION\n");
>@@ -8906,6 +8907,13 @@ check_param_for_creating_dumpfile(int argc, char *argv[])
> */
> info->name_memory = argv[optind];
>
>+ } else if ((argc == optind + 1) && info->flag_mem_usage) {
>+ /*
>+ * Parameter for showing the page number of memory
>+ * in different use from.
>+ */
>+ info->name_memory = argv[optind];
>+
> } else
> return FALSE;
>
>@@ -9148,6 +9156,58 @@ static int get_sys_kernel_vmcoreinfo(uint64_t *addr, uint64_t *len)
> return 0;
> }
>
>+int show_mem_usage(void)
>+{
>+ uint64_t vmcoreinfo_addr, vmcoreinfo_len;
>+
>+ if (!is_crashkernel_mem_reserved()) {
>+ ERRMSG("No memory is reserved for crashkenrel!\n");
>+ return FALSE;
>+ }
>+
>+
>+ if (!info->flag_cyclic)
>+ info->flag_cyclic = TRUE;
>+
>+ info->dump_level = MAX_DUMP_LEVEL;
>+
>+ if (!get_page_offset())
>+ return FALSE;
>+
>+ if (!open_dump_memory())
>+ return FALSE;
>+
>+ if (!get_elf_loads(info->fd_memory, info->name_memory))
>+ return FALSE;
>+
>+ if (get_sys_kernel_vmcoreinfo(&vmcoreinfo_addr, &vmcoreinfo_len))
>+ return FALSE;
>+
>+ if (!set_kcore_vmcoreinfo(vmcoreinfo_addr, vmcoreinfo_len))
>+ return FALSE;
>+
>+ if (!get_kcore_dump_loads())
>+ return FALSE;
>+
>+ if (!initial())
>+ return FALSE;
>+
>+
>+ if (!prepare_bitmap2_buffer_cyclic())
>+ return FALSE;
>+
>+ info->num_dumpable = get_num_dumpable_cyclic();
>+
>+ free_bitmap2_buffer_cyclic();
>+
>+ print_mem_usage();
>+
>+ if (!close_files_for_creating_dumpfile())
>+ return FALSE;
>+
>+ return TRUE;
>+}
>+
>
> static struct option longopts[] = {
> {"split", no_argument, NULL, OPT_SPLIT},
>@@ -9165,6 +9225,7 @@ static struct option longopts[] = {
> {"cyclic-buffer", required_argument, NULL, OPT_CYCLIC_BUFFER},
> {"eppic", required_argument, NULL, OPT_EPPIC},
> {"non-mmap", no_argument, NULL, OPT_NON_MMAP},
>+ {"mem-usage", no_argument, NULL, OPT_MEM_USAGE},
> {0, 0, 0, 0}
> };
>
>@@ -9256,6 +9317,9 @@ main(int argc, char *argv[])
> case OPT_DUMP_DMESG:
> info->flag_dmesg = 1;
> break;
>+ case OPT_MEM_USAGE:
>+ info->flag_mem_usage = 1;
>+ break;
> case OPT_COMPRESS_SNAPPY:
> info->flag_compress = DUMP_DH_COMPRESSED_SNAPPY;
> break;
>@@ -9396,6 +9460,18 @@ main(int argc, char *argv[])
>
> MSG("\n");
> MSG("The dmesg log is saved to %s.\n", info->name_dumpfile);
>+ } else if (info->flag_mem_usage) {
>+ if (!check_param_for_creating_dumpfile(argc, argv)) {
>+ MSG("Commandline parameter is invalid.\n");
>+ MSG("Try `makedumpfile --help' for more information.\n");
>+ goto out;
>+ }
>+
>+ if (!show_mem_usage())
>+ goto out;
>+
>+ MSG("\n");
>+ MSG("Showing page number of memory in different use successfully.\n");
> } else {
> if (!check_param_for_creating_dumpfile(argc, argv)) {
> MSG("Commandline parameter is invalid.\n");
>diff --git a/makedumpfile.h b/makedumpfile.h
>index 8881c76..ba8c0f9 100644
>--- a/makedumpfile.h
>+++ b/makedumpfile.h
>@@ -911,6 +911,7 @@ struct DumpInfo {
> int flag_force; /* overwrite existing stuff */
> int flag_exclude_xen_dom;/* exclude Domain-U from xen-kdump */
> int flag_dmesg; /* dump the dmesg log out of the vmcore file */
>+ int flag_mem_usage; /*show the page number of memory in different use*/
> int flag_use_printk_log; /* did we read printk_log symbol name? */
> int flag_nospace; /* the flag of "No space on device" error */
> int flag_vmemmap; /* kernel supports vmemmap address space */
>@@ -1772,6 +1773,7 @@ struct elf_prstatus {
> #define OPT_CYCLIC_BUFFER OPT_START+11
> #define OPT_EPPIC OPT_START+12
> #define OPT_NON_MMAP OPT_START+13
>+#define OPT_MEM_USAGE OPT_START+14
>
> /*
> * Function Prototype.
>diff --git a/print_info.c b/print_info.c
>index 7592690..29db918 100644
>--- a/print_info.c
>+++ b/print_info.c
>@@ -264,6 +264,14 @@ print_usage(void)
> MSG(" LOGFILE. If a VMCORE does not contain VMCOREINFO for dmesg, it is\n");
> MSG(" necessary to specfiy [-x VMLINUX] or [-i VMCOREINFO].\n");
> MSG("\n");
>+ MSG(" [--mem-usage]:\n");
>+ MSG(" This option is used to show the page numbers of current system in different\n");
>+ MSG(" use. It should be executed in 1st kernel. By the help of this, user can know\n");
>+ MSG(" how many pages is dumpable when different dump_level is specified. It analyzes\n");
>+ MSG(" the 'System Ram' and 'kernel text' program segment of /proc/kcore excluding\n");
>+ MSG(" the crashkernel range, then calculates the page number of different kind per\n");
>+ MSG(" vmcoreinfo. So currently /proc/kcore need be specified explicitly.\n");
>+ MSG("\n");
> MSG(" [-D]:\n");
> MSG(" Print debugging message.\n");
> MSG("\n");
>--
>1.8.5.3
