Messages in this thread |  | | Date | Tue, 9 Oct 2001 22:57:52 -0700 (PDT) | From | "Jeffrey W. Baker" <> | Subject | Test of 2.4.11 versus 2.4.10-ac10 |
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I compared the two leading kernels at the moment: 2.4.11 and 2.4.10-ac10. The latter of course has Rik's VM while the former uses AA's. I used a simple test which simulates the loads I am interested in. One process randomly seeks in a 1GB file, reading 16MB chunks, then seeks again and writes a 16MB chunk, then fsync()s the file. The other process allocates increasingly larger amounts of memory and reads and writes them a few times. The interesting thing happens when this second process starts to use nearly all the physical memory in the machine.
I made a few subjective observations about the kernels. Both of them made progress under heavy swap + I/O loads, where kernels before 2.4.10 would uniformly livelock in kswapd. 2.4.10-ac10 seemed to have better interactive performance under swap. Switching xterms and using Galeon was faster under 2.4.10-ac10 than under 2.4.11. Both systems were usable under swap, which again is a huge departure from past 2.4 kernels.
2.4.10-ac10 seems to sometimes have lengthy stalls in certain cases. When doing fast sequential I/O (building the 1GB file used in this test for example), I/O always proceeded but sometimes the X pointer would stick for 1-2 seconds at a stretch. 2.4.10-ac10 also seems to bounce off the upper limit of memory: if the disk cache approaches the limit of physical memory, everything will stop for up to 1 second while the kernel recalims some RAM. Then the cache starts to run up again. Hence the "bounce".
2.4.10-ac10 seems to have better disk I/O under stress. This may be due to VM or elevator changes. In any case updatedb finished much more quickly under a swap load than did 2.4.11.
My tests were run on a 1.4GHz Athlon CPU with 256 MB main memory and 256 MB swap. Storage is a 2-disk software RAID-1 attached to an aic7xxx host adapter. This is also where swap lives. File system is ext2.
The source for my two tests is attached, as well as the output for both running simultaneously on the respective kernels ([io|flip]-[ac|linus].log). I hope someone finds this useful.
The only hard conclusion I came to was that the AA VM deals with low memory situations more sanely. On 2.4.10-ac10, the 236MB test took 161 seconds. The 238MB test was killed after 5 minutes. 2.4.11 proceeded through 244MB at a constant 134 second pace before I just killed it from boredom.
I'd love to make some charts here but my Gnumeric is too old. If someone makes any, please send me a few PNG files of them. Note that you can make a time chart of I/O by multiplying the throughput numbers by 16MB to find how long the iteration took.
-jwb #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/time.h>
#define MEGABYTE 1048576
int main (void) { unsigned int i; void *a = NULL; void *b = NULL; struct timeval ts; struct timeval te;
for (i = 1; i <= 200; i++) { gettimeofday(&ts, NULL); printf("Start two blocks of %d megabytes\n", i); a = realloc(a, i * MEGABYTE); b = realloc(b, i * MEGABYTE); if (NULL == a || NULL == b) exit(EXIT_FAILURE); memset(a, '0', i * MEGABYTE); memset(b, '1', i * MEGABYTE); memcpy(b, a, i * MEGABYTE); gettimeofday(&te, NULL); printf("Elapsed: %.2f sec\n", te.tv_sec - ts.tv_sec + (te.tv_usec - ts.tv_usec)/1000000.0);
fflush(stdout); } exit(EXIT_SUCCESS); } #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/time.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <unistd.h> #include <sys/mman.h>
#define MEGABYTE 1048576
int main (void) { int fd; unsigned long int r; void *m; void *p; void *b; struct timeval ts; struct timeval te; float e; fd = open("/home/jwb/bigfile", O_RDWR); if (-1 == fd) exit(EXIT_FAILURE); m = mmap(0, 1024 * MEGABYTE, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); if (NULL == m) exit(EXIT_FAILURE); b = malloc(16 * MEGABYTE); if (NULL == b) exit(EXIT_FAILURE); srand(1); for (;;) { r = (unsigned long int)((1024.0 - 16.0) * MEGABYTE * rand() / RAND_MAX + 0.0); p = m + r;
gettimeofday(&ts, NULL); memcpy(b, p, 16 * MEGABYTE); gettimeofday(&te, NULL);
e = te.tv_sec - ts.tv_sec + (te.tv_usec - ts.tv_usec)/1000000.0; printf("Read: %.2f MB/sec\n", 16/e); r = (unsigned long int)((1024.0 - 16.0) * MEGABYTE * rand() / RAND_MAX + 0.0); p = m + r;
gettimeofday(&ts, NULL); memset(p, '1', 16 * MEGABYTE); fsync(fd); gettimeofday(&te, NULL); e = te.tv_sec - ts.tv_sec + (te.tv_usec - ts.tv_usec)/1000000.0; printf("Write: %.2f MB/sec\n", 16/e); fflush(stdout); } exit(EXIT_SUCCESS); } Read: 26.89 MB/sec Write: 27.45 MB/sec Read: 24.53 MB/sec Write: 32.89 MB/sec Read: 33.69 MB/sec Write: 23.55 MB/sec Read: 27.17 MB/sec Write: 21.62 MB/sec Read: 50.23 MB/sec Write: 21.66 MB/sec Read: 26.74 MB/sec Write: 27.89 MB/sec Read: 9.44 MB/sec Write: 9.66 MB/sec Read: 26.98 MB/sec Write: 56.47 MB/sec Read: 25.35 MB/sec Write: 3.74 MB/sec Read: 22.07 MB/sec Write: 17.60 MB/sec Read: 9.28 MB/sec Write: 7.37 MB/sec Read: 36.24 MB/sec Write: 12.91 MB/sec Read: 10.14 MB/sec Write: 9.63 MB/sec Read: 9.65 MB/sec Write: 6.25 MB/sec Read: 19.20 MB/sec Write: 16.90 MB/sec Read: 13.47 MB/sec Write: 9.02 MB/sec Read: 11.52 MB/sec Write: 11.11 MB/sec Read: 23.30 MB/sec Write: 10.04 MB/sec Read: 7.39 MB/sec Write: 24.48 MB/sec Read: 9.71 MB/sec Write: 7.97 MB/sec Read: 9.41 MB/sec Write: 125.09 MB/sec Read: 5.98 MB/sec Write: 21.75 MB/sec Read: 3.90 MB/sec Write: 23.07 MB/sec Read: 2.47 MB/sec Write: 8.06 MB/sec Read: 2.84 MB/sec Write: 5.99 MB/sec Read: 1.48 MB/sec Write: 2.65 MB/sec Read: 1.74 MB/sec Write: 5.00 MB/sec Read: 2.67 MB/sec Write: 10.44 MB/sec Read: 2.98 MB/sec Write: 7.90 MB/sec Read: 4.67 MB/sec Write: 6.08 MB/sec Read: 10.12 MB/sec Write: 7.52 MB/sec Read: 5.17 MB/sec Write: 3.00 MB/sec Read: 5.07 MB/sec Write: 11.09 MB/sec Read: 3.32 MB/sec Write: 2.97 MB/sec Read: 5.66 MB/sec Write: 3.68 MB/sec Read: 11.94 MB/sec Write: 4.57 MB/sec Read: 11.08 MB/sec Write: 3.77 MB/sec Read: 41.70 MB/sec Write: 6.82 MB/sec Read: 3.97 MB/sec Write: 4.95 MB/sec Read: 8.67 MB/sec Write: 8.21 MB/sec Read: 5.21 MB/sec Write: 3.60 MB/sec Read: 9.84 MB/sec Write: 3.47 MB/sec Read: 9.06 MB/sec Write: 10.60 MB/sec Read: 5.33 MB/sec Write: 7.97 MB/sec Read: 3.51 MB/sec Write: 4.05 MB/sec Read: 5.11 MB/sec Write: 7.03 MB/sec Read: 9.51 MB/sec Write: 4.63 MB/sec Read: 9.72 MB/sec Write: 6.19 MB/sec Read: 6.35 MB/sec Write: 4.91 MB/sec Read: 45.15 MB/sec Write: 4.58 MB/sec Read: 9.50 MB/sec Write: 6.23 MB/sec Read: 5.60 MB/sec Write: 470.98 MB/sec Read: 8.60 MB/sec Write: 4.33 MB/sec Read: 8.36 MB/sec Write: 5.37 MB/sec Read: 11.62 MB/sec Write: 5.13 MB/sec Read: 8.31 MB/sec Write: 5.65 MB/sec Read: 9.34 MB/sec Write: 4.64 MB/sec Read: 4.53 MB/sec Write: 19.92 MB/sec Read: 5.15 MB/sec Write: 5.88 MB/sec Read: 9.64 MB/sec Write: 3.53 MB/sec Read: 8.87 MB/sec Write: 7.13 MB/sec Read: 6.57 MB/sec Write: 4.25 MB/sec Read: 7.54 MB/sec Write: 5.80 MB/sec Read: 7.82 MB/sec Write: 4.00 MB/sec Read: 11.68 MB/sec Write: 5.65 MB/sec Read: 4.18 MB/sec Write: 7.11 MB/sec Read: 6.19 MB/sec Write: 7.76 MB/sec Read: 7.40 MB/sec Write: 4.38 MB/sec Read: 7.11 MB/sec Write: 3.14 MB/sec Read: 14.46 MB/sec Write: 7.72 MB/sec Read: 5.49 MB/sec Write: 3.95 MB/sec Read: 9.06 MB/sec Write: 3.49 MB/sec Read: 11.58 MB/sec Write: 8.48 MB/sec Read: 22.35 MB/sec Write: 5.92 MB/sec Read: 4.83 MB/sec Write: 7.61 MB/sec Read: 5.88 MB/sec Write: 3.31 MB/sec Read: 4.11 MB/sec Write: 13.83 MB/sec Start two blocks of 1 megabytes Elapsed: 0.03 sec Start two blocks of 2 megabytes Elapsed: 0.02 sec Start two blocks of 3 megabytes Elapsed: 0.03 sec Start two blocks of 4 megabytes Elapsed: 0.03 sec Start two blocks of 5 megabytes Elapsed: 0.04 sec Start two blocks of 6 megabytes Elapsed: 0.06 sec Start two blocks of 7 megabytes Elapsed: 0.06 sec Start two blocks of 8 megabytes Elapsed: 0.08 sec Start two blocks of 9 megabytes Elapsed: 0.12 sec Start two blocks of 10 megabytes Elapsed: 0.09 sec Start two blocks of 11 megabytes Elapsed: 0.10 sec Start two blocks of 12 megabytes Elapsed: 0.13 sec Start two blocks of 13 megabytes Elapsed: 0.11 sec Start two blocks of 14 megabytes Elapsed: 0.12 sec Start two blocks of 15 megabytes Elapsed: 0.12 sec Start two blocks of 16 megabytes Elapsed: 0.13 sec Start two blocks of 17 megabytes Elapsed: 0.14 sec Start two blocks of 18 megabytes Elapsed: 0.15 sec Start two blocks of 19 megabytes Elapsed: 0.15 sec Start two blocks of 20 megabytes Elapsed: 0.18 sec Start two blocks of 21 megabytes Elapsed: 0.17 sec Start two blocks of 22 megabytes Elapsed: 0.20 sec Start two blocks of 23 megabytes Elapsed: 0.21 sec Start two blocks of 24 megabytes Elapsed: 0.22 sec Start two blocks of 25 megabytes Elapsed: 0.23 sec Start two blocks of 26 megabytes Elapsed: 0.24 sec Start two blocks of 27 megabytes Elapsed: 0.26 sec Start two blocks of 28 megabytes Elapsed: 0.30 sec Start two blocks of 29 megabytes Elapsed: 0.26 sec Start two blocks of 30 megabytes Elapsed: 0.27 sec Start two blocks of 31 megabytes Elapsed: 0.33 sec Start two blocks of 32 megabytes Elapsed: 0.33 sec Start two blocks of 33 megabytes Elapsed: 0.36 sec Start two blocks of 34 megabytes Elapsed: 0.39 sec Start two blocks of 35 megabytes Elapsed: 0.33 sec Start two blocks of 36 megabytes Elapsed: 0.37 sec Start two blocks of 37 megabytes Elapsed: 0.42 sec Start two blocks of 38 megabytes Elapsed: 0.44 sec Start two blocks of 39 megabytes Elapsed: 0.39 sec Start two blocks of 40 megabytes Elapsed: 0.39 sec Start two blocks of 41 megabytes Elapsed: 0.47 sec Start two blocks of 42 megabytes Elapsed: 0.61 sec Start two blocks of 43 megabytes Elapsed: 0.42 sec Start two blocks of 44 megabytes Elapsed: 0.41 sec Start two blocks of 45 megabytes Elapsed: 0.41 sec Start two blocks of 46 megabytes Elapsed: 0.50 sec Start two blocks of 47 megabytes Elapsed: 0.46 sec Start two blocks of 48 megabytes Elapsed: 0.50 sec Start two blocks of 49 megabytes Elapsed: 0.45 sec Start two blocks of 50 megabytes Elapsed: 0.48 sec Start two blocks of 51 megabytes Elapsed: 0.52 sec Start two blocks of 52 megabytes Elapsed: 0.49 sec Start two blocks of 53 megabytes Elapsed: 0.55 sec Start two blocks of 54 megabytes Elapsed: 0.58 sec Start two blocks of 55 megabytes Elapsed: 0.53 sec Start two blocks of 56 megabytes Elapsed: 0.55 sec Start two blocks of 57 megabytes Elapsed: 0.57 sec Start two blocks of 58 megabytes Elapsed: 0.58 sec Start two blocks of 59 megabytes Elapsed: 0.74 sec Start two blocks of 60 megabytes Elapsed: 0.54 sec Start two blocks of 61 megabytes Elapsed: 0.59 sec Start two blocks of 62 megabytes Elapsed: 0.58 sec Start two blocks of 63 megabytes Elapsed: 0.57 sec Start two blocks of 64 megabytes Elapsed: 0.59 sec Start two blocks of 65 megabytes Elapsed: 0.61 sec Start two blocks of 66 megabytes Elapsed: 0.71 sec Start two blocks of 67 megabytes Elapsed: 0.62 sec Start two blocks of 68 megabytes Elapsed: 0.70 sec Start two blocks of 69 megabytes Elapsed: 0.60 sec Start two blocks of 70 megabytes Elapsed: 0.61 sec Start two blocks of 71 megabytes Elapsed: 0.61 sec Start two blocks of 72 megabytes Elapsed: 0.63 sec Start two blocks of 73 megabytes Elapsed: 0.72 sec Start two blocks of 74 megabytes Elapsed: 0.69 sec Start two blocks of 75 megabytes Elapsed: 0.83 sec Start two blocks of 76 megabytes Elapsed: 0.65 sec Start two blocks of 77 megabytes Elapsed: 0.70 sec Start two blocks of 78 megabytes Elapsed: 0.71 sec Start two blocks of 79 megabytes Elapsed: 0.82 sec Start two blocks of 80 megabytes Elapsed: 0.66 sec Start two blocks of 81 megabytes Elapsed: 0.77 sec Start two blocks of 82 megabytes Elapsed: 0.89 sec Start two blocks of 83 megabytes Elapsed: 0.73 sec Start two blocks of 84 megabytes Elapsed: 0.75 sec Start two blocks of 85 megabytes Elapsed: 0.81 sec Start two blocks of 86 megabytes Elapsed: 0.74 sec Start two blocks of 87 megabytes Elapsed: 0.76 sec Start two blocks of 88 megabytes Elapsed: 0.94 sec Start two blocks of 89 megabytes Elapsed: 0.92 sec Start two blocks of 90 megabytes Elapsed: 0.76 sec Start two blocks of 91 megabytes Elapsed: 0.77 sec Start two blocks of 92 megabytes Elapsed: 0.86 sec Start two blocks of 93 megabytes Elapsed: 0.93 sec Start two blocks of 94 megabytes Elapsed: 0.92 sec Start two blocks of 95 megabytes Elapsed: 0.82 sec Start two blocks of 96 megabytes Elapsed: 0.86 sec Start two blocks of 97 megabytes Elapsed: 0.85 sec Start two blocks of 98 megabytes Elapsed: 0.95 sec Start two blocks of 99 megabytes Elapsed: 0.91 sec Start two blocks of 100 megabytes Elapsed: 0.90 sec Start two blocks of 101 megabytes Elapsed: 0.93 sec Start two blocks of 102 megabytes Elapsed: 0.85 sec Start two blocks of 103 megabytes Elapsed: 0.84 sec Start two blocks of 104 megabytes Elapsed: 1.00 sec Start two blocks of 105 megabytes Elapsed: 1.06 sec Start two blocks of 106 megabytes Elapsed: 0.98 sec Start two blocks of 107 megabytes Elapsed: 1.00 sec Start two blocks of 108 megabytes Elapsed: 1.01 sec Start two blocks of 109 megabytes Elapsed: 1.07 sec Start two blocks of 110 megabytes Elapsed: 1.07 sec Start two blocks of 111 megabytes Elapsed: 1.11 sec Start two blocks of 112 megabytes Elapsed: 1.09 sec Start two blocks of 113 megabytes Elapsed: 1.43 sec Start two blocks of 114 megabytes Elapsed: 1.63 sec Start two blocks of 115 megabytes Elapsed: 1.20 sec Start two blocks of 116 megabytes Elapsed: 2.59 sec Start two blocks of 117 megabytes Elapsed: 36.36 sec Start two blocks of 118 megabytes Elapsed: 160.58 sec Read: 26.50 MB/sec Write: 25.84 MB/sec Read: 21.98 MB/sec Write: 22.87 MB/sec Read: 21.26 MB/sec Write: 22.66 MB/sec Read: 27.36 MB/sec Write: 18.86 MB/sec Read: 24.85 MB/sec Write: 23.89 MB/sec Read: 24.57 MB/sec Write: 10.84 MB/sec Read: 11.32 MB/sec Write: 22.86 MB/sec Read: 18.99 MB/sec Write: 23.84 MB/sec Read: 30.57 MB/sec Write: 23.16 MB/sec Read: 5.65 MB/sec Write: 8.59 MB/sec Read: 10.38 MB/sec Write: 10.89 MB/sec Read: 27.52 MB/sec Write: 5.49 MB/sec Read: 7.35 MB/sec Write: 18.67 MB/sec Read: 30.51 MB/sec Write: 9.70 MB/sec Read: 6.84 MB/sec Write: 16.30 MB/sec Read: 21.42 MB/sec Write: 7.67 MB/sec Read: 13.62 MB/sec Write: 7.88 MB/sec Read: 13.11 MB/sec Write: 16.17 MB/sec Read: 9.65 MB/sec Write: 8.22 MB/sec Read: 20.79 MB/sec Write: 10.09 MB/sec Read: 7.25 MB/sec Write: 15.90 MB/sec Read: 17.29 MB/sec Write: 12.13 MB/sec Read: 16.36 MB/sec Write: 6.63 MB/sec Read: 3.06 MB/sec Write: 9.55 MB/sec Read: 3.74 MB/sec Write: 15.90 MB/sec Read: 2.73 MB/sec Write: 11.06 MB/sec Read: 1.38 MB/sec Write: 3.57 MB/sec Read: 1.42 MB/sec Write: 4.01 MB/sec Read: 2.27 MB/sec Write: 3.95 MB/sec Read: 3.26 MB/sec Write: 4.27 MB/sec Read: 6.87 MB/sec Write: 2.49 MB/sec Read: 2.92 MB/sec Write: 7.83 MB/sec Read: 3.82 MB/sec Write: 4.21 MB/sec Read: 5.90 MB/sec Write: 5.04 MB/sec Read: 6.48 MB/sec Write: 5.32 MB/sec Read: 7.19 MB/sec Write: 1.88 MB/sec Read: 8.58 MB/sec Write: 8.54 MB/sec Read: 56.24 MB/sec Write: 5.99 MB/sec Read: 4.35 MB/sec Write: 4.96 MB/sec Read: 3.74 MB/sec Write: 4.64 MB/sec Read: 3.77 MB/sec Write: 2.76 MB/sec Read: 3.71 MB/sec Write: 4.34 MB/sec Read: 8.25 MB/sec Write: 3.62 MB/sec Read: 4.12 MB/sec Write: 4.04 MB/sec Read: 4.36 MB/sec Write: 8.70 MB/sec Read: 4.74 MB/sec Write: 3.18 MB/sec Read: 3.29 MB/sec Write: 4.88 MB/sec Read: 5.52 MB/sec Write: 4.52 MB/sec Read: 3.43 MB/sec Write: 9.57 MB/sec Read: 15.85 MB/sec Write: 7.77 MB/sec Read: 4.96 MB/sec Write: 4.96 MB/sec Read: 3.34 MB/sec Write: 5.80 MB/sec Read: 7.31 MB/sec Write: 6.56 MB/sec Read: 3.07 MB/sec Write: 4.13 MB/sec Read: 3.62 MB/sec Write: 7.78 MB/sec Read: 4.47 MB/sec Write: 3.67 MB/sec Read: 3.35 MB/sec Write: 4.91 MB/sec Read: 4.05 MB/sec Write: 6.17 MB/sec Read: 5.24 MB/sec Write: 4.09 MB/sec Read: 4.50 MB/sec Write: 3.39 MB/sec Read: 6.67 MB/sec Write: 4.53 MB/sec Read: 5.11 MB/sec Write: 2.38 MB/sec Read: 3.95 MB/sec Write: 3.63 MB/sec Read: 4.35 MB/sec Write: 4.63 MB/sec Read: 8.18 MB/sec Write: 4.85 MB/sec Read: 5.13 MB/sec Write: 3.48 MB/sec Read: 2.58 MB/sec Write: 9.64 MB/sec Read: 5.06 MB/sec Write: 7.12 MB/sec Read: 3.55 MB/sec Write: 5.02 MB/sec Read: 9.66 MB/sec Write: 4.24 MB/sec Read: 5.94 MB/sec Write: 5.09 MB/sec Read: 3.54 MB/sec Write: 3.40 MB/sec Read: 8.68 MB/sec Write: 5.68 MB/sec Read: 11.75 MB/sec Write: 4.29 MB/sec Read: 3.51 MB/sec Write: 6.65 MB/sec Read: 6.43 MB/sec Write: 3.70 MB/sec Read: 3.57 MB/sec Write: 2.73 MB/sec Read: 6.04 MB/sec Write: 4.55 MB/sec Read: 5.31 MB/sec Write: 3.70 MB/sec Read: 2.98 MB/sec Write: 3.76 MB/sec Read: 4.25 MB/sec Write: 3.66 MB/sec Read: 3.29 MB/sec Write: 3.92 MB/sec Read: 5.88 MB/sec Write: 6.19 MB/sec Read: 3.53 MB/sec Write: 3.78 MB/sec Read: 15.74 MB/sec Write: 19.24 MB/sec Read: 4.71 MB/sec Write: 4.62 MB/sec Read: 3.91 MB/sec Write: 2.89 MB/sec Read: 5.10 MB/sec Write: 3.81 MB/sec Read: 5.77 MB/sec Write: 9.29 MB/sec Read: 8.09 MB/sec Write: 4.28 MB/sec Read: 6.23 MB/sec Write: 4.66 MB/sec Read: 5.57 MB/sec Write: 3.37 MB/sec Read: 3.12 MB/sec Write: 7.11 MB/sec Read: 6.11 MB/sec Write: 4.21 MB/sec Read: 6.41 MB/sec Write: 2.98 MB/sec Read: 10.55 MB/sec Write: 3.59 MB/sec Read: 11.47 MB/sec Write: 4.67 MB/sec Read: 3.84 MB/sec Write: 161.19 MB/sec Read: 2.54 MB/sec Write: 7.23 MB/sec Read: 26.37 MB/sec Write: 24.11 MB/sec Read: 2.81 MB/sec Write: 8.52 MB/sec Read: 5.30 MB/sec Write: 48.64 MB/sec Read: 19.60 MB/sec Write: 26.45 MB/sec Read: 27.57 MB/sec Write: 89.77 MB/sec Read: 23.34 MB/sec Write: 21.57 MB/sec Read: 16.76 MB/sec Write: 9.14 MB/sec Start two blocks of 1 megabytes Elapsed: 0.01 sec Start two blocks of 2 megabytes Elapsed: 0.03 sec Start two blocks of 3 megabytes Elapsed: 0.08 sec Start two blocks of 4 megabytes Elapsed: 0.36 sec Start two blocks of 5 megabytes Elapsed: 0.06 sec Start two blocks of 6 megabytes Elapsed: 0.07 sec Start two blocks of 7 megabytes Elapsed: 0.14 sec Start two blocks of 8 megabytes Elapsed: 0.28 sec Start two blocks of 9 megabytes Elapsed: 0.28 sec Start two blocks of 10 megabytes Elapsed: 0.09 sec Start two blocks of 11 megabytes Elapsed: 0.10 sec Start two blocks of 12 megabytes Elapsed: 0.14 sec Start two blocks of 13 megabytes Elapsed: 0.14 sec Start two blocks of 14 megabytes Elapsed: 0.21 sec Start two blocks of 15 megabytes Elapsed: 0.14 sec Start two blocks of 16 megabytes Elapsed: 0.15 sec Start two blocks of 17 megabytes Elapsed: 0.23 sec Start two blocks of 18 megabytes Elapsed: 0.26 sec Start two blocks of 19 megabytes Elapsed: 0.28 sec Start two blocks of 20 megabytes Elapsed: 0.20 sec Start two blocks of 21 megabytes Elapsed: 0.22 sec Start two blocks of 22 megabytes Elapsed: 0.27 sec Start two blocks of 23 megabytes Elapsed: 0.35 sec Start two blocks of 24 megabytes Elapsed: 0.25 sec Start two blocks of 25 megabytes Elapsed: 0.25 sec Start two blocks of 26 megabytes Elapsed: 0.27 sec Start two blocks of 27 megabytes Elapsed: 0.32 sec Start two blocks of 28 megabytes Elapsed: 0.32 sec Start two blocks of 29 megabytes Elapsed: 0.35 sec Start two blocks of 30 megabytes Elapsed: 0.47 sec Start two blocks of 31 megabytes Elapsed: 0.33 sec Start two blocks of 32 megabytes Elapsed: 0.37 sec Start two blocks of 33 megabytes Elapsed: 0.38 sec Start two blocks of 34 megabytes Elapsed: 0.34 sec Start two blocks of 35 megabytes Elapsed: 0.34 sec Start two blocks of 36 megabytes Elapsed: 0.40 sec Start two blocks of 37 megabytes Elapsed: 0.35 sec Start two blocks of 38 megabytes Elapsed: 0.46 sec Start two blocks of 39 megabytes Elapsed: 0.39 sec Start two blocks of 40 megabytes Elapsed: 0.40 sec Start two blocks of 41 megabytes Elapsed: 0.47 sec Start two blocks of 42 megabytes Elapsed: 0.43 sec Start two blocks of 43 megabytes Elapsed: 0.48 sec Start two blocks of 44 megabytes Elapsed: 0.43 sec Start two blocks of 45 megabytes Elapsed: 0.55 sec Start two blocks of 46 megabytes Elapsed: 0.51 sec Start two blocks of 47 megabytes Elapsed: 0.60 sec Start two blocks of 48 megabytes Elapsed: 0.50 sec Start two blocks of 49 megabytes Elapsed: 0.54 sec Start two blocks of 50 megabytes Elapsed: 0.49 sec Start two blocks of 51 megabytes Elapsed: 0.55 sec Start two blocks of 52 megabytes Elapsed: 0.51 sec Start two blocks of 53 megabytes Elapsed: 0.59 sec Start two blocks of 54 megabytes Elapsed: 0.55 sec Start two blocks of 55 megabytes Elapsed: 0.61 sec Start two blocks of 56 megabytes Elapsed: 0.63 sec Start two blocks of 57 megabytes Elapsed: 0.69 sec Start two blocks of 58 megabytes Elapsed: 0.62 sec Start two blocks of 59 megabytes Elapsed: 0.58 sec Start two blocks of 60 megabytes Elapsed: 0.64 sec Start two blocks of 61 megabytes Elapsed: 0.67 sec Start two blocks of 62 megabytes Elapsed: 0.67 sec Start two blocks of 63 megabytes Elapsed: 0.61 sec Start two blocks of 64 megabytes Elapsed: 0.57 sec Start two blocks of 65 megabytes Elapsed: 0.63 sec Start two blocks of 66 megabytes Elapsed: 0.61 sec Start two blocks of 67 megabytes Elapsed: 0.70 sec Start two blocks of 68 megabytes Elapsed: 0.68 sec Start two blocks of 69 megabytes Elapsed: 0.61 sec Start two blocks of 70 megabytes Elapsed: 0.68 sec Start two blocks of 71 megabytes Elapsed: 0.66 sec Start two blocks of 72 megabytes Elapsed: 0.68 sec Start two blocks of 73 megabytes Elapsed: 0.70 sec Start two blocks of 74 megabytes Elapsed: 0.68 sec Start two blocks of 75 megabytes Elapsed: 0.77 sec Start two blocks of 76 megabytes Elapsed: 0.72 sec Start two blocks of 77 megabytes Elapsed: 0.70 sec Start two blocks of 78 megabytes Elapsed: 0.74 sec Start two blocks of 79 megabytes Elapsed: 0.73 sec Start two blocks of 80 megabytes Elapsed: 0.76 sec Start two blocks of 81 megabytes Elapsed: 0.69 sec Start two blocks of 82 megabytes Elapsed: 0.82 sec Start two blocks of 83 megabytes Elapsed: 0.77 sec Start two blocks of 84 megabytes Elapsed: 0.82 sec Start two blocks of 85 megabytes Elapsed: 0.84 sec Start two blocks of 86 megabytes Elapsed: 0.81 sec Start two blocks of 87 megabytes Elapsed: 0.75 sec Start two blocks of 88 megabytes Elapsed: 0.82 sec Start two blocks of 89 megabytes Elapsed: 0.77 sec Start two blocks of 90 megabytes Elapsed: 0.83 sec Start two blocks of 91 megabytes Elapsed: 0.84 sec Start two blocks of 92 megabytes Elapsed: 0.82 sec Start two blocks of 93 megabytes Elapsed: 0.78 sec Start two blocks of 94 megabytes Elapsed: 0.84 sec Start two blocks of 95 megabytes Elapsed: 0.85 sec Start two blocks of 96 megabytes Elapsed: 0.88 sec Start two blocks of 97 megabytes Elapsed: 0.90 sec Start two blocks of 98 megabytes Elapsed: 0.85 sec Start two blocks of 99 megabytes Elapsed: 0.90 sec Start two blocks of 100 megabytes Elapsed: 0.90 sec Start two blocks of 101 megabytes Elapsed: 0.89 sec Start two blocks of 102 megabytes Elapsed: 0.92 sec Start two blocks of 103 megabytes Elapsed: 0.92 sec Start two blocks of 104 megabytes Elapsed: 0.94 sec Start two blocks of 105 megabytes Elapsed: 0.94 sec Start two blocks of 106 megabytes Elapsed: 0.93 sec Start two blocks of 107 megabytes Elapsed: 0.96 sec Start two blocks of 108 megabytes Elapsed: 0.92 sec Start two blocks of 109 megabytes Elapsed: 0.99 sec Start two blocks of 110 megabytes Elapsed: 1.02 sec Start two blocks of 111 megabytes Elapsed: 1.14 sec Start two blocks of 112 megabytes Elapsed: 1.00 sec Start two blocks of 113 megabytes Elapsed: 0.98 sec Start two blocks of 114 megabytes Elapsed: 1.00 sec Start two blocks of 115 megabytes Elapsed: 1.02 sec Start two blocks of 116 megabytes Elapsed: 0.99 sec Start two blocks of 117 megabytes Elapsed: 0.98 sec Start two blocks of 118 megabytes Elapsed: 3.27 sec Start two blocks of 119 megabytes Elapsed: 73.43 sec Start two blocks of 120 megabytes Elapsed: 135.97 sec Start two blocks of 121 megabytes Elapsed: 130.02 sec Start two blocks of 122 megabytes Elapsed: 137.57 sec
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