Chapter 193: Thresholds and Measures

He fell asleep at 2:40 a.m. and was dragged awake by his body clock at 6:20. No alarm. Lin Chen opened his eyes, and the watermark stains on the ceiling looked gray-white in the morning light. A dull pain came from his left ankle, like a rusted hinge being forced open. He sat up without getting out of bed right away. First he flexed his toes, then rubbed his calf with his palm. His muscles were stiff, but the blood was starting to flow again. He threw back the blanket and hopped to the bathroom on one foot. Cold water splashed over his face. In the mirror, the whites of his eyes were veined with red, his jaw drawn tight. He switched on the electric toothbrush, and its buzzing filled the cramped space.

Back at the desk, the hardcover notebook lay open. Last night’s entry still ended on the final line. He picked up his pen and added a timestamp:

“00:05–02:30. Abnormal crawler alert. Traced logs. Created new rule-cleaning document. Rested 3.5 hours.”

The pen paused. He crossed out sleep and replaced it with rest. Sleep was a luxury; rest was the physiological minimum. He pulled open the drawer and took out a box of instant coffee. Tore one open. Poured it into a mug. Added hot water. The bitterness mingled with the scent of cheap artificial flavoring. He took a sip, and a mild burn rose in his stomach.

He turned on the computer. The terminal window still held the log-analysis script from last night. He brought up Abnormal Traffic Interception and Cost Offset Plan. The framework of the document was already there; now it needed flesh. The core logic was simple enough: place interception rules ahead of the WAF layer and apply dynamic rate limiting to high-frequency scraping patterns. The hard part was calibration. If the rules were too strict, they might block legitimate overseas proxies or price-comparison plugins; too loose, and the bill for elastic scaling would devour this month’s performance bonus.

He pulled the access logs from the past thirty days and ran a clustering analysis in Python. The result came back: requests from that IP range were concentrated on SKU parameters and price fields on product detail pages, arriving at fixed 1.2-second intervals. The User-Agent headers masqueraded as mainstream browsers, but the Accept-Language header was missing. Typical machine behavior.

He typed out a draft of the rules:

“1. For IPs with missing Accept-Language and request frequency > 50/minute, trigger CAPTCHA interception; 2. After three CAPTCHA failures, add to temporary blacklist (TTL 2 hours); 3. Traffic hitting these rules will not count toward elastic scaling thresholds and will be calculated separately.”

After writing that, he opened the cloud provider console and ran a simulated stress test. The curve stayed steady. Estimated costs dropped by 12%. He exported the document as a PDF, attached screenshots of the test data, and submitted it to the security team through the internal ticketing system. CC: Director Li.

At ten in the morning, the ticket status changed to Accepted.

At eleven-thirty, a DingTalk message from Director Li popped up:

“Come to my office.”

Lin Chen closed his laptop. When he stood, his left foot touched the ground and pain shot up along his Achilles tendon. He shifted his weight and slowed his pace. The hallway air-conditioning was running hard. In his thin shirt, his arms prickled with a fine layer of gooseflesh. He pushed open the director’s office door. Director Li was staring at dual monitors, twirling a fountain pen in one hand. Printed PPT slides and cost models lay spread across the desk.

“Sit.” Director Li didn’t look up. “I’ve read the crawler rules. The logic is fine. But the security team says CAPTCHA interception will add front-end loading delay—about two hundred milliseconds. During major promotions, conversion is sensitive to latency. Have you calculated the loss?”

Lin Chen sat down, back straight. “I have. A two-hundred-millisecond delay is expected to increase bounce rate by 0.3%. But if we don’t intercept, peak crawler traffic stacked on top of business traffic will push scaling costs 40% over budget. A 0.3% conversion loss translates into controllable marketing expense. A 40% overrun hits the department’s profit red line. I choose the former.”

Director Li stopped twirling the pen and looked up at him. There was no praise in his eyes, only assessment.

“What data supports that?”

“The AB test records from the last three promotional events. The elasticity coefficient between latency and conversion is 0.0015. It’s on page three of the ticket attachment.”

His voice was steady, flat, without any rise or fall.

Director Li flipped to the attachment. Read for two minutes. Closed the folder.

“All right. We’ll go with your plan. But on Friday, during the defense, if Old Chen asks about latency losses, you answer for it yourself.”

“Understood.”

“And one more thing.” Director Li paused. “You’re taking leave on Wednesday. Make sure your handoff is clean. Don’t leave loose ends.”

“The handoff document is already sorted. Monitoring permissions for the core chain have been transferred to Zhou Wei. I left both my mobile and backup landline as emergency contacts.”

Director Li nodded. “Go on, then. Don’t drop the ball on Friday.”

Back at his desk, Lin Chen opened the drawer and took out a canvas document pouch. Inside were his mother’s medical records from the past two years, test reports, and copies of her health insurance card. He checked them one by one and arranged them in chronological order. One item was missing: last month’s electromyography report. He made a note to get a duplicate from the hospital tomorrow.

He opened his mobile banking app. Balance: 682.5. He transferred 300 to his mother’s card.

“Backup for the recheck. Tell me if it’s not enough.”

Sent.

The screen dimmed.

At two in the afternoon, the security team replied to the ticket:

“The rule has been gradually rolled out. Monitoring shows 94% interception rate, 0.1% false positive rate. Latency increased by 180ms. In line with expectations. Cost model has been updated accordingly.”

Lin Chen replied:

“Received. Thank you.”

He closed the ticket page and opened the PPT. He replaced the bar chart on the cost forecast slide with the latest data. The red warning line dropped another notch. The logic loop was complete. He saved it, then backed it up both to the local drive and the cloud.

At six in the evening, people around the office began leaving one after another. Lin Chen did not move. He still needed to go through the defense script one more time. Not memorization—simulation. What would Old Chen ask? The boundaries of downgrade strategy? Health indicators for rolling back the gray release? Cost hedging for abnormal traffic? He listed the possible questions in the hardcover notebook and wrote out the answers one by one. No polished phrasing, only data and logic.

At 7:40, he closed the notebook and stood. His left foot had gone numb enough that he could no longer feel pain, which was a dangerous sign. He walked to the fire stairwell. No one was there. Leaning against the wall, he rotated his ankle. One circle. Two. The joint gave a faint click. He took a deep breath and shifted all his weight onto his left leg. Five seconds. Ten. The muscles began to tremble. He pulled the foot back, returned to his desk, and packed his bag: laptop, charger, hardcover notebook, document pouch. The zipper closed. The weight settled onto his right shoulder.

On the subway ride home, the carriage was crowded. He gripped the handrail, swaying with the train. The glass reflected his face. Tired, but his eyes were clear. He thought of the old house in Qingshi Village, of his mother’s stooped back as she simmered medicine at the stove. Those memories were not sentimental; they were simply facts. Facts did not need embellishment. They only needed to be faced.

At nine that night, in the rental room, he boiled a bowl of hanging noodles and cracked in two eggs. After eating, he washed the dishes and dried his hands. The phone screen lit up. Not the work group. A text from the township clinic back home:

“Family of Lin Jianguo: Your mother’s follow-up appointment has been confirmed. Wednesday, 9:00 a.m. Please bring previous medical records. Also: road construction is currently underway in town. Passenger buses may be delayed. It is recommended that you depart two hours early.”

Lin Chen stared at the screen.

Road construction. Bus delays.

Train G1422 was due to arrive at 8:15 a.m. If the bus ran late, he would miss the pickup. He opened the ticketing app and checked the earliest high-speed train. G1420, arrival 6:30. Fare: forty-five more.

He tapped Pay.

Remaining balance: 337.5.

He set down the phone and walked to the window. Night wind slipped in through the crack, carrying the city’s particular smell of dust. He took out the hardcover notebook, turned to a fresh page, and wrote:

“5/15. Rebooked to G1420. Pick up at the station earlier. Friday defense. Bottom line: no collapse.”

The pen paused. Then he added another line:

“Old Chen’s stress-test traffic will be stacked with the security team’s interception rules tomorrow. Need to rerun the peak curve. Arrive at the office by 7 a.m.”

Outside the window, the streetlights came on one by one. Halos spread across the glass. He drew the curtains, lay down, and closed his eyes. His breathing gradually steadied.

There was another battle tomorrow.

But tonight, he had to get enough sleep first.

His body was the only capital he had.

Once the gears meshed, they could not stop.