On 04/14/16 at 01:56pm, "Zhou, Wenjian/???" wrote: > Hello Atsushi, > > I calculated the memory cost of each thread, and the result is about 50KB. > But I find each thread will take a little more than 100KB actually. > And I set the reserved memory for each thread to 200KB in this version. > > I think 200KB is a proper value. Hi, Zhou. Is there a general formular provided to user to calculate rough reserved memory, if option num-threads is used? Thanks Minfei > > -- > Thanks > Zhou > > On 04/14/2016 01:42 PM, Zhou Wenjian wrote: > >v6: > > 1. address Atsushi Kumagai's comments about calculating and reserving memory > >v5: > > 1. remove unused variable check_out > > 2. reset num_threads if memory is not enough > >v4: > > 1. fix a bug caused by the logic > >v3: > > 1. remove some unused variables > > 2. fix a bug caused by the wrong logic > > 3. fix a bug caused by optimising > > 4. improve more performance by using Minoru Usui's code > > > >multi-threads implementation will introduce extra cost when handling > >each page. The origin implementation will also do the extra work for > >filtered pages. So there is a big performance degradation in > >--num-threads -d 31. > >The new implementation won't do the extra work for filtered pages any > >more. So the performance of -d 31 is close to that of serial processing. > > > >The new implementation is just like the following: > > * The basic idea is producer producing page and consumer writing page. > > * Each producer have a page_flag_buf list which is used for storing > > page's description. > > * The size of page_flag_buf is little so it won't take too much memory. > > * And all producers will share a page_data_buf array which is > > used for storing page's compressed data. > > * The main thread is the consumer. It will find the next pfn and write > > it into file. > > * The next pfn is smallest pfn in all page_flag_buf. > > > >Signed-off-by: Minoru Usui <min-usui at ti.jp.nec.com> > >Signed-off-by: Zhou Wenjian <zhouwj-fnst at cn.fujitsu.com> > >--- > > makedumpfile.c | 320 +++++++++++++++++++++++++++++++++------------------------ > > makedumpfile.h | 38 ++++--- > > 2 files changed, 210 insertions(+), 148 deletions(-) > > > >diff --git a/makedumpfile.c b/makedumpfile.c > >index fa0b779..a826321 100644 > >--- a/makedumpfile.c > >+++ b/makedumpfile.c > >@@ -3481,9 +3481,8 @@ initial_for_parallel() > > { > > unsigned long len_buf_out; > > unsigned long page_data_buf_size; > >- unsigned long limit_size; > >- int page_data_num; > >- int i; > >+ struct page_flag *current; > >+ int i, j; > > > > len_buf_out = calculate_len_buf_out(info->page_size); > > > >@@ -3553,20 +3552,7 @@ initial_for_parallel() > > #endif > > } > > > >- /* > >- * get a safe number of page_data > >- */ > >- page_data_buf_size = MAX(len_buf_out, info->page_size); > >- > >- limit_size = (get_free_memory_size() > >- - MAP_REGION * info->num_threads) * 0.6; > >- > >- page_data_num = limit_size / page_data_buf_size; > >- > >- info->num_buffers = MIN(NUM_BUFFERS, page_data_num); > >- > >- DEBUG_MSG("Number of struct page_data for produce/consume: %d\n", > >- info->num_buffers); > >+ info->num_buffers = PAGE_DATA_NUM * info->num_threads; > > > > /* > > * allocate memory for page_data > >@@ -3579,6 +3565,7 @@ initial_for_parallel() > > } > > memset(info->page_data_buf, 0, sizeof(struct page_data) * info->num_buffers); > > > >+ page_data_buf_size = MAX(len_buf_out, info->page_size); > > for (i = 0; i < info->num_buffers; i++) { > > if ((info->page_data_buf[i].buf = malloc(page_data_buf_size)) == NULL) { > > MSG("Can't allocate memory for buf of page_data_buf. %s\n", > >@@ -3588,6 +3575,36 @@ initial_for_parallel() > > } > > > > /* > >+ * initial page_flag for each thread > >+ */ > >+ if ((info->page_flag_buf = malloc(sizeof(void *) * info->num_threads)) > >+ == NULL) { > >+ MSG("Can't allocate memory for page_flag_buf. %s\n", > >+ strerror(errno)); > >+ return FALSE; > >+ } > >+ memset(info->page_flag_buf, 0, sizeof(void *) * info->num_threads); > >+ > >+ for (i = 0; i < info->num_threads; i++) { > >+ if ((info->page_flag_buf[i] = calloc(1, sizeof(struct page_flag))) == NULL) { > >+ MSG("Can't allocate memory for page_flag. %s\n", > >+ strerror(errno)); > >+ return FALSE; > >+ } > >+ current = info->page_flag_buf[i]; > >+ > >+ for (j = 1; j < PAGE_FLAG_NUM; j++) { > >+ if ((current->next = calloc(1, sizeof(struct page_flag))) == NULL) { > >+ MSG("Can't allocate memory for page_flag. %s\n", > >+ strerror(errno)); > >+ return FALSE; > >+ } > >+ current = current->next; > >+ } > >+ current->next = info->page_flag_buf[i]; > >+ } > >+ > >+ /* > > * initial fd_memory for threads > > */ > > for (i = 0; i < info->num_threads; i++) { > >@@ -3612,7 +3629,8 @@ initial_for_parallel() > > void > > free_for_parallel() > > { > >- int i; > >+ int i, j; > >+ struct page_flag *current; > > > > if (info->threads != NULL) { > > for (i = 0; i < info->num_threads; i++) { > >@@ -3655,6 +3673,19 @@ free_for_parallel() > > free(info->page_data_buf); > > } > > > >+ if (info->page_flag_buf != NULL) { > >+ for (i = 0; i < info->num_threads; i++) { > >+ for (j = 0; j < PAGE_FLAG_NUM; j++) { > >+ if (info->page_flag_buf[i] != NULL) { > >+ current = info->page_flag_buf[i]; > >+ info->page_flag_buf[i] = current->next; > >+ free(current); > >+ } > >+ } > >+ } > >+ free(info->page_flag_buf); > >+ } > >+ > > if (info->parallel_info == NULL) > > return; > > > >@@ -7075,11 +7106,11 @@ void * > > kdump_thread_function_cyclic(void *arg) { > > void *retval = PTHREAD_FAIL; > > struct thread_args *kdump_thread_args = (struct thread_args *)arg; > >- struct page_data *page_data_buf = kdump_thread_args->page_data_buf; > >+ volatile struct page_data *page_data_buf = kdump_thread_args->page_data_buf; > >+ volatile struct page_flag *page_flag_buf = kdump_thread_args->page_flag_buf; > > struct cycle *cycle = kdump_thread_args->cycle; > >- int page_data_num = kdump_thread_args->page_data_num; > >- mdf_pfn_t pfn; > >- int index; > >+ mdf_pfn_t pfn = cycle->start_pfn; > >+ int index = kdump_thread_args->thread_num; > > int buf_ready; > > int dumpable; > > int fd_memory = 0; > >@@ -7125,47 +7156,48 @@ kdump_thread_function_cyclic(void *arg) { > > kdump_thread_args->thread_num); > > } > > > >- while (1) { > >- /* get next pfn */ > >- pthread_mutex_lock(&info->current_pfn_mutex); > >- pfn = info->current_pfn; > >- info->current_pfn++; > >- pthread_mutex_unlock(&info->current_pfn_mutex); > >- > >- if (pfn >= kdump_thread_args->end_pfn) > >- break; > >- > >- index = -1; > >+ /* > >+ * filtered page won't take anything > >+ * unfiltered zero page will only take a page_flag_buf > >+ * unfiltered non-zero page will take a page_flag_buf and a page_data_buf > >+ */ > >+ while (pfn < cycle->end_pfn) { > > buf_ready = FALSE; > > > >+ pthread_mutex_lock(&info->page_data_mutex); > >+ while (page_data_buf[index].used != FALSE) { > >+ index = (index + 1) % info->num_buffers; > >+ } > >+ page_data_buf[index].used = TRUE; > >+ pthread_mutex_unlock(&info->page_data_mutex); > >+ > > while (buf_ready == FALSE) { > > pthread_testcancel(); > >- > >- index = pfn % page_data_num; > >- > >- if (pfn - info->consumed_pfn > info->num_buffers) > >+ if (page_flag_buf->ready == FLAG_READY) > > continue; > > > >- if (page_data_buf[index].ready != 0) > >- continue; > >- > >- pthread_mutex_lock(&page_data_buf[index].mutex); > >- > >- if (page_data_buf[index].ready != 0) > >- goto unlock; > >- > >- buf_ready = TRUE; > >+ /* get next dumpable pfn */ > >+ pthread_mutex_lock(&info->current_pfn_mutex); > >+ for (pfn = info->current_pfn; pfn < cycle->end_pfn; pfn++) { > >+ dumpable = is_dumpable( > >+ info->fd_bitmap ? &bitmap_parallel : info->bitmap2, > >+ pfn, > >+ cycle); > >+ if (dumpable) > >+ break; > >+ } > >+ info->current_pfn = pfn + 1; > > > >- page_data_buf[index].pfn = pfn; > >- page_data_buf[index].ready = 1; > >+ page_flag_buf->pfn = pfn; > >+ page_flag_buf->ready = FLAG_FILLING; > >+ pthread_mutex_unlock(&info->current_pfn_mutex); > >+ sem_post(&info->page_flag_buf_sem); > > > >- dumpable = is_dumpable( > >- info->fd_bitmap ? &bitmap_parallel : info->bitmap2, > >- pfn, > >- cycle); > >- page_data_buf[index].dumpable = dumpable; > >- if (!dumpable) > >- goto unlock; > >+ if (pfn >= cycle->end_pfn) { > >+ info->current_pfn = cycle->end_pfn; > >+ page_data_buf[index].used = FALSE; > >+ break; > >+ } > > > > if (!read_pfn_parallel(fd_memory, pfn, buf, > > &bitmap_memory_parallel, > >@@ -7178,11 +7210,11 @@ kdump_thread_function_cyclic(void *arg) { > > > > if ((info->dump_level & DL_EXCLUDE_ZERO) > > && is_zero_page(buf, info->page_size)) { > >- page_data_buf[index].zero = TRUE; > >- goto unlock; > >+ page_flag_buf->zero = TRUE; > >+ goto next; > > } > > > >- page_data_buf[index].zero = FALSE; > >+ page_flag_buf->zero = FALSE; > > > > /* > > * Compress the page data. > >@@ -7232,12 +7264,14 @@ kdump_thread_function_cyclic(void *arg) { > > page_data_buf[index].size = info->page_size; > > memcpy(page_data_buf[index].buf, buf, info->page_size); > > } > >-unlock: > >- pthread_mutex_unlock(&page_data_buf[index].mutex); > >+ page_flag_buf->index = index; > >+ buf_ready = TRUE; > >+next: > >+ page_flag_buf->ready = FLAG_READY; > >+ page_flag_buf = page_flag_buf->next; > > > > } > > } > >- > > retval = NULL; > > > > fail: > >@@ -7265,14 +7299,15 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header, > > struct page_desc pd; > > struct timeval tv_start; > > struct timeval last, new; > >- unsigned long long consuming_pfn; > > pthread_t **threads = NULL; > > struct thread_args *kdump_thread_args = NULL; > > void *thread_result; > >- int page_data_num; > >+ int page_buf_num; > > struct page_data *page_data_buf = NULL; > > int i; > > int index; > >+ int end_count, consuming; > >+ mdf_pfn_t current_pfn, temp_pfn; > > > > if (info->flag_elf_dumpfile) > > return FALSE; > >@@ -7284,13 +7319,6 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header, > > goto out; > > } > > > >- res = pthread_mutex_init(&info->consumed_pfn_mutex, NULL); > >- if (res != 0) { > >- ERRMSG("Can't initialize consumed_pfn_mutex. %s\n", > >- strerror(res)); > >- goto out; > >- } > >- > > res = pthread_mutex_init(&info->filter_mutex, NULL); > > if (res != 0) { > > ERRMSG("Can't initialize filter_mutex. %s\n", strerror(res)); > >@@ -7314,36 +7342,23 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header, > > end_pfn = cycle->end_pfn; > > > > info->current_pfn = start_pfn; > >- info->consumed_pfn = start_pfn - 1; > > > > threads = info->threads; > > kdump_thread_args = info->kdump_thread_args; > > > >- page_data_num = info->num_buffers; > >+ page_buf_num = info->num_buffers; > > page_data_buf = info->page_data_buf; > >+ pthread_mutex_init(&info->page_data_mutex, NULL); > >+ sem_init(&info->page_flag_buf_sem, 0, 0); > > > >- for (i = 0; i < page_data_num; i++) { > >- /* > >- * producer will use pfn in page_data_buf to decide the > >- * consumed pfn > >- */ > >- page_data_buf[i].pfn = start_pfn - 1; > >- page_data_buf[i].ready = 0; > >- res = pthread_mutex_init(&page_data_buf[i].mutex, NULL); > >- if (res != 0) { > >- ERRMSG("Can't initialize mutex of page_data_buf. %s\n", > >- strerror(res)); > >- goto out; > >- } > >- } > >+ for (i = 0; i < page_buf_num; i++) > >+ page_data_buf[i].used = FALSE; > > > > for (i = 0; i < info->num_threads; i++) { > > kdump_thread_args[i].thread_num = i; > > kdump_thread_args[i].len_buf_out = len_buf_out; > >- kdump_thread_args[i].start_pfn = start_pfn; > >- kdump_thread_args[i].end_pfn = end_pfn; > >- kdump_thread_args[i].page_data_num = page_data_num; > > kdump_thread_args[i].page_data_buf = page_data_buf; > >+ kdump_thread_args[i].page_flag_buf = info->page_flag_buf[i]; > > kdump_thread_args[i].cycle = cycle; > > > > res = pthread_create(threads[i], NULL, > >@@ -7356,55 +7371,86 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header, > > } > > } > > > >- consuming_pfn = start_pfn; > >- index = -1; > >+ end_count = 0; > >+ while (1) { > >+ consuming = 0; > > > >- gettimeofday(&last, NULL); > >+ /* > >+ * The basic idea is producer producing page and consumer writing page. > >+ * Each producer have a page_flag_buf list which is used for storing page's description. > >+ * The size of page_flag_buf is little so it won't take too much memory. > >+ * And all producers will share a page_data_buf array which is used for storing page's compressed data. > >+ * The main thread is the consumer. It will find the next pfn and write it into file. > >+ * The next pfn is smallest pfn in all page_flag_buf. > >+ */ > >+ sem_wait(&info->page_flag_buf_sem); > >+ gettimeofday(&last, NULL); > >+ while (1) { > >+ current_pfn = end_pfn; > > > >- while (consuming_pfn < end_pfn) { > >- index = consuming_pfn % page_data_num; > >+ /* > >+ * page_flag_buf is in circular linked list. > >+ * The array info->page_flag_buf[] records the current page_flag_buf in each thread's > >+ * page_flag_buf list. > >+ * consuming is used for recording in which thread the pfn is the smallest. > >+ * current_pfn is used for recording the value of pfn when checking the pfn. > >+ */ > >+ for (i = 0; i < info->num_threads; i++) { > >+ if (info->page_flag_buf[i]->ready == FLAG_UNUSED) > >+ continue; > >+ temp_pfn = info->page_flag_buf[i]->pfn; > > > >- gettimeofday(&new, NULL); > >- if (new.tv_sec - last.tv_sec > WAIT_TIME) { > >- ERRMSG("Can't get data of pfn %llx.\n", consuming_pfn); > >- goto out; > >- } > >+ /* > >+ * count how many threads have reached the end. > >+ */ > >+ if (temp_pfn >= end_pfn) { > >+ info->page_flag_buf[i]->ready = FLAG_UNUSED; > >+ end_count++; > >+ continue; > >+ } > > > >- /* > >- * check pfn first without mutex locked to reduce the time > >- * trying to lock the mutex > >- */ > >- if (page_data_buf[index].pfn != consuming_pfn) > >- continue; > >+ if (current_pfn < temp_pfn) > >+ continue; > > > >- if (pthread_mutex_trylock(&page_data_buf[index].mutex) != 0) > >- continue; > >+ consuming = i; > >+ current_pfn = temp_pfn; > >+ } > > > >- /* check whether the found one is ready to be consumed */ > >- if (page_data_buf[index].pfn != consuming_pfn || > >- page_data_buf[index].ready != 1) { > >- goto unlock; > >+ /* > >+ * If all the threads have reached the end, we will finish writing. > >+ */ > >+ if (end_count >= info->num_threads) > >+ goto finish; > >+ > >+ /* > >+ * If the page_flag_buf is not ready, the pfn recorded may be changed. > >+ * So we should recheck. > >+ */ > >+ if (info->page_flag_buf[consuming]->ready != FLAG_READY) { > >+ gettimeofday(&new, NULL); > >+ if (new.tv_sec - last.tv_sec > WAIT_TIME) { > >+ ERRMSG("Can't get data of pfn.\n"); > >+ goto out; > >+ } > >+ continue; > >+ } > >+ > >+ if (current_pfn == info->page_flag_buf[consuming]->pfn) > >+ break; > > } > > > > if ((num_dumped % per) == 0) > > print_progress(PROGRESS_COPY, num_dumped, info->num_dumpable); > > > >- /* next pfn is found, refresh last here */ > >- last = new; > >- consuming_pfn++; > >- info->consumed_pfn++; > >- page_data_buf[index].ready = 0; > >- > >- if (page_data_buf[index].dumpable == FALSE) > >- goto unlock; > >- > > num_dumped++; > > > >- if (page_data_buf[index].zero == TRUE) { > >+ > >+ if (info->page_flag_buf[consuming]->zero == TRUE) { > > if (!write_cache(cd_header, pd_zero, sizeof(page_desc_t))) > > goto out; > > pfn_zero++; > > } else { > >+ index = info->page_flag_buf[consuming]->index; > > pd.flags = page_data_buf[index].flags; > > pd.size = page_data_buf[index].size; > > pd.page_flags = 0; > >@@ -7420,12 +7466,12 @@ write_kdump_pages_parallel_cyclic(struct cache_data *cd_header, > > */ > > if (!write_cache(cd_page, page_data_buf[index].buf, pd.size)) > > goto out; > >- > >+ page_data_buf[index].used = FALSE; > > } > >-unlock: > >- pthread_mutex_unlock(&page_data_buf[index].mutex); > >+ info->page_flag_buf[consuming]->ready = FLAG_UNUSED; > >+ info->page_flag_buf[consuming] = info->page_flag_buf[consuming]->next; > > } > >- > >+finish: > > ret = TRUE; > > /* > > * print [100 %] > >@@ -7463,15 +7509,9 @@ out: > > } > > } > > > >- if (page_data_buf != NULL) { > >- for (i = 0; i < page_data_num; i++) { > >- pthread_mutex_destroy(&page_data_buf[i].mutex); > >- } > >- } > >- > >+ sem_destroy(&info->page_flag_buf_sem); > > pthread_rwlock_destroy(&info->usemmap_rwlock); > > pthread_mutex_destroy(&info->filter_mutex); > >- pthread_mutex_destroy(&info->consumed_pfn_mutex); > > pthread_mutex_destroy(&info->current_pfn_mutex); > > > > return ret; > >@@ -7564,6 +7604,7 @@ write_kdump_pages_cyclic(struct cache_data *cd_header, struct cache_data *cd_pag > > num_dumped++; > > if (!read_pfn(pfn, buf)) > > goto out; > >+ > > filter_data_buffer(buf, pfn_to_paddr(pfn), info->page_size); > > > > /* > >@@ -10201,7 +10242,6 @@ out: > > return free_size; > > } > > > >- > > /* > > * Choose the less value of the three below as the size of cyclic buffer. > > * - the size enough for storing the 1st or 2nd bitmap for the whole of vmcore > >@@ -10223,6 +10263,20 @@ calculate_cyclic_buffer_size(void) { > > * free memory for safety. > > */ > > limit_size = get_free_memory_size() * 0.6; > >+ > >+ /* > >+ * Recalculate the limit_size according to num_threads. > >+ * And reset num_threads if there is not enough memory. > >+ */ > >+ if (limit_size - maximum_size < THREAD_REGION * info->num_threads) { > >+ MSG("There isn't enough memory for %d threads.\n", info->num_threads); > >+ > >+ info->num_threads = MAX(0, limit_size - maximum_size) / THREAD_REGION; > >+ MSG("--num_threads is set to %d.\n", info->num_threads); > >+ } > >+ > >+ limit_size = limit_size - THREAD_REGION * info->num_threads; > >+ > > /* Try to keep both 1st and 2nd bitmap at the same time. */ > > bitmap_size = info->max_mapnr * 2 / BITPERBYTE; > > > >diff --git a/makedumpfile.h b/makedumpfile.h > >index e0b5bbf..322d31b 100644 > >--- a/makedumpfile.h > >+++ b/makedumpfile.h > >@@ -44,6 +44,7 @@ > > #include "print_info.h" > > #include "sadump_mod.h" > > #include <pthread.h> > >+#include <semaphore.h> > > > > /* > > * Result of command > >@@ -974,10 +975,11 @@ typedef unsigned long long int ulonglong; > > * for parallel process > > */ > > > >-#define PAGE_DATA_NUM (50) > >+#define PAGE_FLAG_NUM (20) > >+#define PAGE_DATA_NUM (5) > > #define WAIT_TIME (60 * 10) > > #define PTHREAD_FAIL ((void *)-2) > >-#define NUM_BUFFERS (50) > >+#define THREAD_REGION (200 * 1024) > > > > struct mmap_cache { > > char *mmap_buf; > >@@ -985,28 +987,33 @@ struct mmap_cache { > > off_t mmap_end_offset; > > }; > > > >+enum { > >+ FLAG_UNUSED, > >+ FLAG_READY, > >+ FLAG_FILLING > >+}; > >+struct page_flag { > >+ mdf_pfn_t pfn; > >+ char zero; > >+ char ready; > >+ short index; > >+ struct page_flag *next; > >+}; > >+ > > struct page_data > > { > >- mdf_pfn_t pfn; > >- int dumpable; > >- int zero; > >- unsigned int flags; > > long size; > > unsigned char *buf; > >- pthread_mutex_t mutex; > >- /* > >- * whether the page_data is ready to be consumed > >- */ > >- int ready; > >+ int flags; > >+ int used; > > }; > > > > struct thread_args { > > int thread_num; > > unsigned long len_buf_out; > >- mdf_pfn_t start_pfn, end_pfn; > >- int page_data_num; > > struct cycle *cycle; > > struct page_data *page_data_buf; > >+ struct page_flag *page_flag_buf; > > }; > > > > /* > >@@ -1295,11 +1302,12 @@ struct DumpInfo { > > pthread_t **threads; > > struct thread_args *kdump_thread_args; > > struct page_data *page_data_buf; > >+ struct page_flag **page_flag_buf; > >+ sem_t page_flag_buf_sem; > > pthread_rwlock_t usemmap_rwlock; > > mdf_pfn_t current_pfn; > > pthread_mutex_t current_pfn_mutex; > >- mdf_pfn_t consumed_pfn; > >- pthread_mutex_t consumed_pfn_mutex; > >+ pthread_mutex_t page_data_mutex; > > pthread_mutex_t filter_mutex; > > }; > > extern struct DumpInfo *info; > > > > > > _______________________________________________ > kexec mailing list > kexec at lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec