JMeter 使用終極線程組時的頻率峰值

Question

我在 JMeter 中使用 Ultimate Thread Group 進行性能測試。 結合計時器，我想動態擴展用戶/線程的數量，同時每個用戶都有一個恆定的吞吐量，例如 10 個請求/秒。

當 Ultimate Thread Group 增加用戶數時，每秒總請求率會在短時間內出現高峰。 高峰過后，請求率符合預期。

例如，我得到以下跟蹤：Start with 40 users, 10 requests per second for each user: 40 * 10 = 400 requests/second 。 將用戶數增加到 60 個，我預計60 * 10 = 600 個請求/秒，但一開始我的峰值超過3959 個請求/秒。

summary = 366401 in 00:15:16 =  400.0/s Avg:     1 Min:     0 Max:  1071 Err:     0 (0.00%)
summary +  12000 in 00:00:30 =  400.0/s Avg:     1 Min:     0 Max:    20 Err:     0 (0.00%) Active: 40 Started: 40 Finished: 0
summary = 378401 in 00:15:46 =  400.0/s Avg:     1 Min:     0 Max:  1071 Err:     0 (0.00%)
summary +  12000 in 00:00:30 =  400.0/s Avg:     1 Min:     0 Max:    44 Err:     0 (0.00%) Active: 40 Started: 40 Finished: 0
summary = 390401 in 00:16:16 =  400.0/s Avg:     1 Min:     0 Max:  1071 Err:     0 (0.00%)
summary +  31784 in 00:00:30 = 1061.9/s Avg:     4 Min:     0 Max:   414 Err:     0 (0.00%) Active: 60 Started: 60 Finished: 0
summary = 422185 in 00:16:46 =  419.7/s Avg:     1 Min:     0 Max:  1071 Err:     0 (0.00%)
summary + 118770 in 00:00:30 = 3959.0/s Avg:     5 Min:     0 Max:   493 Err:     0 (0.00%) Active: 60 Started: 60 Finished: 0
summary = 540955 in 00:17:16 =  522.2/s Avg:     2 Min:     0 Max:  1071 Err:     0 (0.00%)
summary +  79419 in 00:00:30 = 2647.3/s Avg:    10 Min:     0 Max:  1435 Err:     0 (0.00%) Active: 60 Started: 60 Finished: 0
summary = 620374 in 00:17:46 =  582.0/s Avg:     3 Min:     0 Max:  1435 Err:     0 (0.00%)
summary +  37227 in 00:00:30 = 1238.1/s Avg:     6 Min:     0 Max:  1354 Err:     0 (0.00%) Active: 60 Started: 60 Finished: 0
summary = 657601 in 00:18:16 =  600.0/s Avg:     3 Min:     0 Max:  1435 Err:     0 (0.00%)
summary +  18000 in 00:00:30 =  600.3/s Avg:     2 Min:     0 Max:   219 Err:     0 (0.00%) Active: 60 Started: 60 Finished: 0
summary = 675601 in 00:18:46 =  600.0/s Avg:     3 Min:     0 Max:  1435 Err:     0 (0.00%)
summary +  18000 in 00:00:30 =  599.9/s Avg:     1 Min:     0 Max:    46 Err:     0 (0.00%) Active: 60 Started: 60 Finished: 0

可視化它看起來像這樣：

有沒有辦法避免這個高峰？ （如果我將用戶數量從 60 增加到 80.80 到 100，我也會達到這個峰值，...）

Answer 1

結合哪個“計時器”？

我認為您為您的場景使用了錯誤的計時器和錯誤的線程組，考慮轉移到並發線程組和吞吐量整形計時器，您可以使用反饋 function連接它們，因此計時器將是驅動負載模式的唯一地方.